# Supplementary Material (ESI) for Perkin Transactions # This journal is © The Royal Society of Chemistry 1999 # CCDC Number: 188/177 #============================================================================== data_global #============================================================================== _audit_creation_date 05-05-99 _audit_creation_method ? _audit_update_record ; ? ; # 1. SUBMISSION DETAILS _publ_contact_author ; T. Oeser Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg ; _publ_contact_author_email 'thomas.oeser@urz.uni-heidelberg.de' _publ_contact_author_fax '(+49) 6221 544205' _publ_contact_author_phone '(+49) 6221 548482' _publ_requested_journal 'J. Chem. Soc. Perkin Trans. 2' _publ_requested_coeditor_name ? _publ_contact_letter ; publication title and authors see below ; # 2. PROCESSING SUMMARY (IUCr Office Use Only) _journal_date_recd_electronic ? _journal_date_to_coeditor ? _journal_date_from_coeditor ? _journal_date_accepted ? _journal_date_printers_first ? _journal_date_printers_final ? _journal_date_proofs_out ? _journal_date_proofs_in ? _journal_coeditor_name ? _journal_coeditor_code ? _journal_coeditor_notes ; ? ; _journal_techeditor_code ? _journal_techeditor_notes ; ? ; _journal_coden_ASTM ? _journal_name_full ? _journal_year ? _journal_volume ? _journal_issue ? _journal_page_first ? _journal_page_last ? _journal_suppl_publ_number ? _journal_suppl_publ_pages ? # 3. TITLE AND AUTHOR LIST _publ_section_title ; Cyclic Diynes with Tetramethyldisilyl Groups in the Bridges. Syntheses and Properties ; # The loop structure below should contain the names and addresses of all # authors, in the required order of publication. Repeat as necessary. loop_ _publ_author_name _publ_author_address 'Haberhauer, Gebhard' #<--'Last name, first name' ; Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg Germany ; 'Gleiter, Rolf' #<--'Last name, first name' ; Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg Germany ; 'Irngartinger, Hermann' #<--'Last name, first name' ; Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg Germany ; 'Oeser, Thomas' #<--'Last name, first name' ; Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg Germany ; 'Rominger, Frank' #<--'Last name, first name' ; Organisch-Chemisches Institut Universit\"at Heidelberg Im Neuenheimer Feld 270 D-69120 Heidelberg Germany ; # 4. TEXT _publ_section_abstract ; ? ; _publ_section_comment ; ? ; _publ_section_experimental ; ? ; _publ_section_references ; Enraf-Nonius, CAD4 Operations Manual, Delft, 1988. International Tables for X-Ray Crystallography, Vol. IV, The Kynoch Press, Birmingham, England, 1974 ; _publ_section_figure_captions ; ? ; _publ_section_acknowledgements ; We thank the Deutsche Forschungsgemeinschaft for financial support of the X-ray diffraction facility. ; data_gh1 _audit_creation_method SHELXL _chemical_name_systematic ; 1,1,2,2-Tetramethyl-1,2-disilacyclodeca-4,8-diyne (8) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_structural ? _chemical_formula_analytical ? _chemical_formula_sum 'C12 H20 Si2' _chemical_formula_weight 220.46 _chemical_melting_point ? _chemical_compound_source ? loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting Orthorhombic _symmetry_space_group_name_H-M C222(1) loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, -y, z+1/2' '-x, y, -z+1/2' 'x, -y, -z' 'x+1/2, y+1/2, z' '-x+1/2, -y+1/2, z+1/2' '-x+1/2, y+1/2, -z+1/2' 'x+1/2, -y+1/2, -z' _cell_length_a 10.1723(8) _cell_length_b 10.5020(8) _cell_length_c 12.9640(10) _cell_angle_alpha 90.00 _cell_angle_beta 90.00 _cell_angle_gamma 90.00 _cell_volume 1384.9(2) _cell_formula_units_Z 4 _cell_measurement_temperature 200(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description fragment _exptl_crystal_colour colourless _exptl_crystal_size_max .31 _exptl_crystal_size_mid .30 _exptl_crystal_size_min .27 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.057 _exptl_crystal_density_method ? _exptl_crystal_F_000 480 _exptl_absorpt_coefficient_mu 0.223 _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.858456 _exptl_absorpt_correction_T_max 0.956241 _exptl_special_details ; ? ; _diffrn_ambient_temperature 200(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device 'Siemens CCD' _diffrn_measurement_method '\w scans' _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 3206 _diffrn_reflns_av_R_equivalents 0.0141 _diffrn_reflns_av_sigmaI/netI 0.0165 _diffrn_reflns_limit_h_min -11 _diffrn_reflns_limit_h_max 11 _diffrn_reflns_limit_k_min -12 _diffrn_reflns_limit_k_max 10 _diffrn_reflns_limit_l_min -13 _diffrn_reflns_limit_l_max 15 _diffrn_reflns_theta_min 2.79 _diffrn_reflns_theta_max 25.47 _reflns_number_total 1181 _reflns_number_observed 1148 _reflns_observed_criterion >2sigma(I) _computing_data_collection 'Siemens XSCANS' _computing_cell_refinement 'Siemens XSCANS' _computing_data_reduction 'Siemens SHELXTL' _computing_structure_solution 'SHELXS-86 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics 'Siemens SHELXTL' _computing_publication_material 'Siemens SHELXTL' _refine_special_details ; Refinement on F^2^ for ALL reflections except for 0 with very negative F^2^ or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The observed criterion of F^2^ > 2sigma(F^2^) is used only for calculating _R_factor_obs etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0470P)^2^+0.0071P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881' _refine_ls_abs_structure_Flack 0.07(12) _refine_ls_number_reflns 1181 _refine_ls_number_parameters 104 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0235 _refine_ls_R_factor_obs 0.0228 _refine_ls_wR_factor_all 0.0614 _refine_ls_wR_factor_obs 0.0607 _refine_ls_goodness_of_fit_all 1.100 _refine_ls_goodness_of_fit_obs 1.105 _refine_ls_restrained_S_all 1.100 _refine_ls_restrained_S_obs 1.105 _refine_ls_shift/esd_max -0.010 _refine_ls_shift/esd_mean 0.002 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_thermal_displace_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_group Si1 Si 0.97282(4) 0.29423(3) 0.66171(3) 0.03223(15) Uani 1 d . . C1 C 0.9737(2) 0.76196(14) 0.69462(12) 0.0422(3) Uani 1 d . . H1A H 1.0504(20) 0.7703(19) 0.6449(16) 0.053(5) Uiso 1 d . . H1B H 0.9167(23) 0.8335(24) 0.6866(17) 0.069(6) Uiso 1 d . . C2 C 0.90688(13) 0.64240(14) 0.66892(11) 0.0366(3) Uani 1 d . . C3 C 0.86532(13) 0.53769(14) 0.65290(11) 0.0346(3) Uani 1 d . . C4 C 0.82881(15) 0.40510(15) 0.63494(12) 0.0380(4) Uani 1 d . . H4A H 0.8037(19) 0.3954(17) 0.5696(17) 0.047(5) Uiso 1 d . . H4B H 0.7558(22) 0.3820(20) 0.6800(17) 0.063(6) Uiso 1 d . . C5 C 1.1161(2) 0.3469(2) 0.58210(13) 0.0425(4) Uani 1 d . . H5A H 1.0920(16) 0.3548(16) 0.5119(15) 0.045(4) Uiso 1 d . . H5B H 1.1849(23) 0.2888(23) 0.5841(18) 0.066(6) Uiso 1 d . . H5C H 1.1412(23) 0.4281(24) 0.6039(18) 0.065(6) Uiso 1 d . . C6 C 0.9198(3) 0.1303(2) 0.6222(2) 0.0575(5) Uani 1 d . . H6A H 0.8375(27) 0.1040(25) 0.6687(20) 0.083(8) Uiso 1 d . . H6B H 0.9800(26) 0.0781(25) 0.6301(19) 0.074(7) Uiso 1 d . . H6C H 0.8908(24) 0.1253(23) 0.5494(23) 0.082(7) Uiso 1 d . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.0436(2) 0.0256(2) 0.0274(2) -0.00066(13) -0.0044(2) -0.00371(15) C1 0.0481(8) 0.0321(8) 0.0464(8) 0.0040(6) 0.0037(7) 0.0012(7) C2 0.0345(7) 0.0393(8) 0.0359(7) 0.0045(7) -0.0001(6) 0.0045(6) C3 0.0294(6) 0.0403(8) 0.0340(7) 0.0050(6) -0.0026(6) 0.0040(6) C4 0.0365(8) 0.0425(8) 0.0349(8) 0.0028(6) -0.0082(6) -0.0071(6) C5 0.0454(9) 0.0455(9) 0.0367(9) 0.0024(7) 0.0000(7) 0.0028(7) C6 0.0895(14) 0.0333(9) 0.0497(10) -0.0073(8) -0.0121(10) -0.0098(10) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C5 1.869(2) . ? Si1 C6 1.875(2) . ? Si1 C4 1.903(2) . ? Si1 Si1 2.3550(7) 3_756 ? C1 C2 1.466(2) . ? C1 C1 1.533(3) 3_756 ? C2 C3 1.196(2) . ? C3 C4 1.460(2) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C5 Si1 C6 110.16(10) . . ? C5 Si1 C4 108.57(7) . . ? C6 Si1 C4 106.90(10) . . ? C5 Si1 Si1 110.71(6) . 3_756 ? C6 Si1 Si1 109.45(6) . 3_756 ? C4 Si1 Si1 110.98(5) . 3_756 ? C2 C1 C1 112.01(10) . 3_756 ? C3 C2 C1 172.11(15) . . ? C2 C3 C4 173.94(14) . . ? C3 C4 Si1 111.02(10) . . ? _refine_diff_density_max 0.274 _refine_diff_density_min -0.126 _refine_diff_density_rms 0.031 #===END data_735H187 _audit_creation_method SHELXL-97 _chemical_name_systematic ; 1,1,2,2-Tetramethyl-1,2-disilacycloundeca-4,9-diyne (9) ; _chemical_name_common ? _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C13 H22 Si2' _chemical_formula_weight 234.49 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M 'C 2/c' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y, -z+1/2' 'x+1/2, y+1/2, z' '-x+1/2, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y, z-1/2' '-x+1/2, -y+1/2, -z' 'x+1/2, -y+1/2, z-1/2' _cell_length_a 13.363(5) _cell_length_b 10.520(2) _cell_length_c 11.258(5) _cell_angle_alpha 90.00 _cell_angle_beta 111.82(3) _cell_angle_gamma 90.00 _cell_volume 1469.2(9) _cell_formula_units_Z 4 _cell_measurement_temperature 223(2) _cell_measurement_reflns_used 25 _cell_measurement_theta_min 10.3 _cell_measurement_theta_max 24.1 _exptl_crystal_description plate _exptl_crystal_colour colourless _exptl_crystal_size_max 0.50 _exptl_crystal_size_mid 0.40 _exptl_crystal_size_min 0.40 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.06 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 512 _exptl_absorpt_coefficient_mu 0.213 _exptl_absorpt_correction_type numerical _exptl_absorpt_correction_T_min 0.901 _exptl_absorpt_correction_T_max 0.920 _exptl_absorpt_process_details ? _exptl_special_details ; ? ; _diffrn_ambient_temperature 223(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type NONIUS_CAD4 _diffrn_measurement_method \w2\q _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_count 100 _diffrn_standards_interval_time 60 _diffrn_standards_decay_% 1 _diffrn_reflns_number 1838 _diffrn_reflns_av_R_equivalents 0.0126 _diffrn_reflns_av_sigmaI/netI 0.0136 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 17 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 13 _diffrn_reflns_limit_l_min -14 _diffrn_reflns_limit_l_max 13 _diffrn_reflns_theta_min 2.54 _diffrn_reflns_theta_max 27.97 _reflns_number_total 1768 _reflns_number_gt 1501 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0644P)^2^+0.6499P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment calculated _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 1768 _refine_ls_number_parameters 75 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.048 _refine_ls_R_factor_gt 0.039 _refine_ls_wR_factor_ref 0.115 _refine_ls_wR_factor_gt 0.109 _refine_ls_goodness_of_fit_ref 1.05 _refine_ls_restrained_S_all 1.05 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si1 Si 0.40842(3) 0.44579(4) 0.18326(4) 0.04425(16) Uani 1 1 d . . . C1 C 0.38971(13) 0.35245(16) 0.03276(14) 0.0533(4) Uani 1 1 d . . . H1A H 0.3158 0.3636 -0.0289 0.064 Uiso 1 1 calc R . . H1B H 0.4392 0.3847 -0.0063 0.064 Uiso 1 1 calc R . . C2 C 0.41057(14) 0.21814(17) 0.06234(16) 0.0562(4) Uani 1 1 d . . . C3 C 0.42596(16) 0.11048(18) 0.09525(18) 0.0648(5) Uani 1 1 d . . . C4 C 0.4429(2) -0.02526(19) 0.1297(2) 0.0855(7) Uani 1 1 d . . . H4A H 0.3862 -0.0525 0.1597 0.103 Uiso 1 1 calc R . . H4B H 0.4334 -0.0736 0.0518 0.103 Uiso 1 1 calc R . . C5 C 0.5369(3) -0.0566(3) 0.2175(5) 0.0684(10) Uani 0.50 1 d P . . H5A H 0.5932 -0.0130 0.1969 0.082 Uiso 0.50 1 calc PR . . H5B H 0.5472 -0.1481 0.2102 0.082 Uiso 0.50 1 calc PR . . C6 C 0.35947(17) 0.61177(18) 0.1355(2) 0.0706(5) Uani 1 1 d . . . H6A H 0.2844 0.6096 0.0782 0.106 Uiso 1 1 calc R . . H6B H 0.4023 0.6511 0.0923 0.106 Uiso 1 1 calc R . . H6C H 0.3663 0.6607 0.2111 0.106 Uiso 1 1 calc R . . C7 C 0.32390(14) 0.3677(2) 0.26177(17) 0.0644(5) Uani 1 1 d . . . H7A H 0.3265 0.4173 0.3355 0.097 Uiso 1 1 calc R . . H7B H 0.3512 0.2829 0.2892 0.097 Uiso 1 1 calc R . . H7C H 0.2500 0.3622 0.2015 0.097 Uiso 1 1 calc R . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.0446(2) 0.0455(3) 0.0431(2) -0.00424(15) 0.01673(17) 0.00149(15) C1 0.0583(9) 0.0604(9) 0.0416(7) -0.0049(6) 0.0190(7) 0.0011(7) C2 0.0622(9) 0.0614(10) 0.0480(8) -0.0158(7) 0.0238(7) -0.0008(7) C3 0.0761(12) 0.0586(10) 0.0646(11) -0.0163(8) 0.0320(9) 0.0000(9) C4 0.1111(19) 0.0509(10) 0.1059(18) -0.0180(11) 0.0534(15) 0.0006(11) C5 0.0558(19) 0.0434(17) 0.098(3) 0.0069(16) 0.0187(19) 0.0079(14) C6 0.0713(11) 0.0561(10) 0.0732(12) -0.0029(9) 0.0136(9) 0.0172(9) C7 0.0565(9) 0.0859(13) 0.0597(10) -0.0165(9) 0.0317(8) -0.0135(9) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C7 1.8638(18) . ? Si1 C6 1.8721(19) . ? Si1 C1 1.8927(17) . ? Si1 Si1 2.3484(13) 2_655 ? C1 C2 1.455(2) . ? C1 H1A 0.9800 . ? C1 H1B 0.9800 . ? C2 C3 1.186(3) . ? C3 C4 1.475(3) . ? C4 C5 1.320(5) . ? C4 H4A 0.9800 . ? C4 H4B 0.9800 . ? C5 C4 1.672(5) 2_655 ? C5 H5A 0.9800 . ? C5 H5B 0.9800 . ? C6 H6A 0.9700 . ? C6 H6B 0.9700 . ? C6 H6C 0.9700 . ? C7 H7A 0.9700 . ? C7 H7B 0.9700 . ? C7 H7C 0.9700 . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C7 Si1 C6 109.80(10) . . ? C7 Si1 C1 107.11(8) . . ? C6 Si1 C1 108.11(9) . . ? C7 Si1 Si1 111.57(7) . 2_655 ? C6 Si1 Si1 110.71(7) . 2_655 ? C1 Si1 Si1 109.41(6) . 2_655 ? C2 C1 Si1 110.40(11) . . ? C2 C1 H1A 109.6 . . ? Si1 C1 H1A 109.6 . . ? C2 C1 H1B 109.6 . . ? Si1 C1 H1B 109.6 . . ? H1A C1 H1B 108.1 . . ? C3 C2 C1 174.66(17) . . ? C2 C3 C4 177.2(2) . . ? C5 C4 C3 116.7(2) . . ? C5 C4 H4A 108.1 . . ? C3 C4 H4A 108.1 . . ? C5 C4 H4B 108.1 . . ? C3 C4 H4B 108.1 . . ? H4A C4 H4B 107.3 . . ? C4 C5 C4 117.8(3) . 2_655 ? C4 C5 H5A 107.9 . . ? C4 C5 H5A 107.9 2_655 . ? C4 C5 H5B 107.9 . . ? C4 C5 H5B 107.9 2_655 . ? H5A C5 H5B 107.2 . . ? Si1 C6 H6A 109.5 . . ? Si1 C6 H6B 109.5 . . ? H6A C6 H6B 109.5 . . ? Si1 C6 H6C 109.5 . . ? H6A C6 H6C 109.5 . . ? H6B C6 H6C 109.5 . . ? Si1 C7 H7A 109.5 . . ? Si1 C7 H7B 109.5 . . ? H7A C7 H7B 109.5 . . ? Si1 C7 H7C 109.5 . . ? H7A C7 H7C 109.5 . . ? H7B C7 H7C 109.5 . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C7 Si1 C1 C2 -52.86(15) . . . . ? C6 Si1 C1 C2 -171.12(12) . . . . ? Si1 Si1 C1 C2 68.23(13) 2_655 . . . ? Si1 C1 C2 C3 22(2) . . . . ? C1 C2 C3 C4 146(4) . . . . ? C2 C3 C4 C5 136(4) . . . . ? C3 C4 C5 C4 76.9(4) . . . 2_655 ? _diffrn_measured_fraction_theta_max 0.996 _diffrn_reflns_theta_full 27.97 _diffrn_measured_fraction_theta_full 0.996 _refine_diff_density_max 0.299 _refine_diff_density_min -0.229 _refine_diff_density_rms 0.047 #===END data_gh6 _audit_creation_method SHELXL _chemical_name_systematic ; 1,1,2,2-Tetramethyl-1,2-disilacyclododeca-4,10-diyne (10) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_structural ? _chemical_formula_analytical ? _chemical_formula_sum 'C14 H24 Si2' _chemical_formula_weight 248.51 _chemical_melting_point ? _chemical_compound_source ? loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting Monoclinic _symmetry_space_group_name_H-M P2(1)/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 10.4260(2) _cell_length_b 12.31510(10) _cell_length_c 13.0649(2) _cell_angle_alpha 90.00 _cell_angle_beta 110.4480(10) _cell_angle_gamma 90.00 _cell_volume 1571.80(4) _cell_formula_units_Z 4 _cell_measurement_temperature 200(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min ? _cell_measurement_theta_max ? _exptl_crystal_description fragment _exptl_crystal_colour colorless _exptl_crystal_size_max .46 _exptl_crystal_size_mid .36 _exptl_crystal_size_min .26 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.050 _exptl_crystal_density_method ? _exptl_crystal_F_000 544 _exptl_absorpt_coefficient_mu 0.203 _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.737649 _exptl_absorpt_correction_T_max 0.962477 _exptl_special_details ; ? ; _diffrn_ambient_temperature 200(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device 'Siemens CCD' _diffrn_measurement_method '\w scans' _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 7035 _diffrn_reflns_av_R_equivalents 0.0170 _diffrn_reflns_av_sigmaI/netI 0.0225 _diffrn_reflns_limit_h_min -8 _diffrn_reflns_limit_h_max 12 _diffrn_reflns_limit_k_min -13 _diffrn_reflns_limit_k_max 14 _diffrn_reflns_limit_l_min -15 _diffrn_reflns_limit_l_max 14 _diffrn_reflns_theta_min 2.08 _diffrn_reflns_theta_max 25.63 _reflns_number_total 2680 _reflns_number_observed 2336 _reflns_observed_criterion >2sigma(I) _computing_data_collection 'Siemens XSCANS' _computing_cell_refinement 'Siemens XSCANS' _computing_data_reduction 'Siemens SHELXTL' _computing_structure_solution 'SHELXS-86 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics 'Siemens SHELXTL' _computing_publication_material 'Siemens SHELXTL' _refine_special_details ; Refinement on F^2^ for ALL reflections except for 0 with very negative F^2^ or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The observed criterion of F^2^ > 2sigma(F^2^) is used only for calculating _R_factor_obs etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0477P)^2^+0.2732P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 2680 _refine_ls_number_parameters 241 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0360 _refine_ls_R_factor_obs 0.0296 _refine_ls_wR_factor_all 0.0795 _refine_ls_wR_factor_obs 0.0755 _refine_ls_goodness_of_fit_all 1.034 _refine_ls_goodness_of_fit_obs 1.060 _refine_ls_restrained_S_all 1.034 _refine_ls_restrained_S_obs 1.060 _refine_ls_shift/esd_max -0.001 _refine_ls_shift/esd_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_thermal_displace_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_group Si1 Si 0.51030(4) 0.96401(3) 0.24145(3) 0.02702(13) Uani 1 d . . Si2 Si 0.69532(4) 0.93065(3) 0.40457(3) 0.02880(13) Uani 1 d . . C3 C 0.7835(2) 1.0624(2) 0.46756(14) 0.0428(4) Uani 1 d . . H3A H 0.7169(19) 1.1073(15) 0.4818(15) 0.049(5) Uiso 1 d . . H3B H 0.8549(22) 1.0428(15) 0.5356(18) 0.058(6) Uiso 1 d . . C4 C 0.8421(2) 1.12255(13) 0.39770(13) 0.0378(4) Uani 1 d . . C5 C 0.8889(2) 1.16979(13) 0.33944(13) 0.0379(4) Uani 1 d . . C6 C 0.9394(2) 1.22321(14) 0.25975(15) 0.0427(4) Uani 1 d . . H6A H 0.8994(19) 1.2988(16) 0.2460(14) 0.051(5) Uiso 1 d . . H6B H 1.0383(20) 1.2311(14) 0.2908(15) 0.048(5) Uiso 1 d . . C7 C 0.8954(2) 1.16099(14) 0.15189(14) 0.0411(4) Uani 1 d . . H7A H 0.9127(18) 1.2060(14) 0.0975(15) 0.046(5) Uiso 1 d . . H7B H 0.8014(19) 1.1486(14) 0.1301(13) 0.040(4) Uiso 1 d . . C8 C 0.9660(2) 1.05151(15) 0.16126(15) 0.0421(4) Uani 1 d . . H8A H 0.9748(16) 1.0177(14) 0.2289(15) 0.036(4) Uiso 1 d . . H8B H 1.0570(20) 1.0618(14) 0.1568(14) 0.048(5) Uiso 1 d . . C9 C 0.8866(2) 0.9716(2) 0.07238(15) 0.0449(4) Uani 1 d . . H9A H 0.9454(20) 0.9067(17) 0.0745(16) 0.059(6) Uiso 1 d . . H9B H 0.8668(18) 1.0046(16) 0.0011(16) 0.048(5) Uiso 1 d . . C10 C 0.7581(2) 0.93772(13) 0.08552(12) 0.0377(4) Uani 1 d . . C11 C 0.6559(2) 0.91408(12) 0.10126(11) 0.0328(3) Uani 1 d . . C12 C 0.5315(2) 0.88624(13) 0.12299(13) 0.0329(3) Uani 1 d . . H12A H 0.4540(20) 0.9025(15) 0.0635(16) 0.047(5) Uiso 1 d . . H12B H 0.5327(18) 0.8108(16) 0.1396(14) 0.049(5) Uiso 1 d . . C13 C 0.4937(2) 1.11125(14) 0.2055(2) 0.0438(4) Uani 1 d . . H13A H 0.4810(22) 1.1487(20) 0.2616(19) 0.074(7) Uiso 1 d . . H13B H 0.5734(25) 1.1411(20) 0.2016(19) 0.080(8) Uiso 1 d . . H13C H 0.4166(25) 1.1231(18) 0.1440(20) 0.076(7) Uiso 1 d . . C14 C 0.3467(2) 0.9135(2) 0.2541(2) 0.0433(4) Uani 1 d . . H14A H 0.3210(25) 0.9555(19) 0.3042(20) 0.081(7) Uiso 1 d . . H14B H 0.2750(28) 0.9219(19) 0.1869(22) 0.087(8) Uiso 1 d . . H14C H 0.3540(25) 0.8407(24) 0.2758(21) 0.090(8) Uiso 1 d . . C15 C 0.6315(2) 0.8679(2) 0.5084(2) 0.0421(4) Uani 1 d . . H15A H 0.5701(21) 0.9145(17) 0.5236(16) 0.060(6) Uiso 1 d . . H15B H 0.5905(24) 0.8022(21) 0.4836(19) 0.077(7) Uiso 1 d . . H15C H 0.7013(24) 0.8562(18) 0.5715(19) 0.070(7) Uiso 1 d . . C16 C 0.8240(2) 0.8381(2) 0.3809(2) 0.0446(4) Uani 1 d . . H16A H 0.8622(23) 0.8707(19) 0.3352(19) 0.075(7) Uiso 1 d . . H16B H 0.7782(26) 0.7714(21) 0.3478(20) 0.084(8) Uiso 1 d . . H16C H 0.8920(27) 0.8227(20) 0.4473(22) 0.087(7) Uiso 1 d . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.0285(2) 0.0239(2) 0.0278(2) -0.00113(15) 0.0088(2) 0.0020(2) Si2 0.0300(2) 0.0308(2) 0.0256(2) 0.0014(2) 0.0097(2) 0.0010(2) C3 0.0478(10) 0.0491(10) 0.0315(9) -0.0067(7) 0.0136(8) -0.0135(8) C4 0.0363(8) 0.0393(9) 0.0344(8) -0.0084(7) 0.0083(7) -0.0094(7) C5 0.0331(8) 0.0379(9) 0.0415(9) -0.0045(7) 0.0113(7) -0.0053(7) C6 0.0365(9) 0.0397(10) 0.0559(11) 0.0024(8) 0.0210(8) -0.0062(7) C7 0.0370(10) 0.0463(10) 0.0434(9) 0.0101(8) 0.0182(8) -0.0029(7) C8 0.0345(9) 0.0540(11) 0.0429(10) 0.0062(8) 0.0200(8) 0.0040(7) C9 0.0496(11) 0.0534(11) 0.0403(10) 0.0018(8) 0.0267(8) 0.0031(8) C10 0.0484(10) 0.0382(9) 0.0286(8) -0.0003(6) 0.0162(7) 0.0022(7) C11 0.0455(9) 0.0293(8) 0.0238(7) -0.0024(6) 0.0124(7) 0.0026(7) C12 0.0385(9) 0.0285(8) 0.0308(8) -0.0030(6) 0.0108(7) -0.0015(7) C13 0.0544(12) 0.0269(8) 0.0418(10) -0.0008(7) 0.0065(9) 0.0057(8) C14 0.0320(9) 0.0472(11) 0.0520(11) -0.0034(9) 0.0162(9) 0.0004(8) C15 0.0550(11) 0.0378(10) 0.0380(10) 0.0076(8) 0.0218(9) 0.0039(9) C16 0.0347(9) 0.0560(12) 0.0406(10) 0.0018(9) 0.0102(8) 0.0132(8) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C13 1.866(2) . ? Si1 C14 1.877(2) . ? Si1 C12 1.8977(15) . ? Si1 Si2 2.3578(5) . ? Si2 C16 1.867(2) . ? Si2 C15 1.874(2) . ? Si2 C3 1.904(2) . ? C3 C4 1.465(2) . ? C3 H3A 0.95(2) . ? C3 H3B 0.97(2) . ? C4 C5 1.190(2) . ? C5 C6 1.476(2) . ? C6 C7 1.527(3) . ? C6 H6A 1.01(2) . ? C6 H6B 0.97(2) . ? C7 C8 1.520(2) . ? C7 H7A 0.97(2) . ? C7 H7B 0.93(2) . ? C8 C9 1.527(3) . ? C8 H8A 0.95(2) . ? C8 H8B 0.98(2) . ? C9 C10 1.470(2) . ? C9 H9A 1.00(2) . ? C9 H9B 0.97(2) . ? C10 C11 1.189(2) . ? C11 C12 1.462(2) . ? C12 H12A 0.93(2) . ? C12 H12B 0.95(2) . ? C13 H13A 0.91(2) . ? C13 H13B 0.93(2) . ? C13 H13C 0.93(3) . ? C14 H14A 0.94(3) . ? C14 H14B 0.94(3) . ? C14 H14C 0.94(3) . ? C15 H15A 0.93(2) . ? C15 H15B 0.92(3) . ? C15 H15C 0.90(2) . ? C16 H16A 0.92(2) . ? C16 H16B 0.97(3) . ? C16 H16C 0.93(3) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C13 Si1 C14 109.71(9) . . ? C13 Si1 C12 108.20(8) . . ? C14 Si1 C12 105.84(8) . . ? C13 Si1 Si2 111.80(6) . . ? C14 Si1 Si2 110.16(7) . . ? C12 Si1 Si2 110.95(5) . . ? C16 Si2 C15 109.01(9) . . ? C16 Si2 C3 108.99(10) . . ? C15 Si2 C3 106.17(8) . . ? C16 Si2 Si1 111.41(6) . . ? C15 Si2 Si1 109.94(7) . . ? C3 Si2 Si1 111.17(6) . . ? C4 C3 Si2 113.90(11) . . ? C4 C3 H3A 108.6(11) . . ? Si2 C3 H3A 107.7(11) . . ? C4 C3 H3B 110.1(12) . . ? Si2 C3 H3B 106.5(12) . . ? H3A C3 H3B 110.1(16) . . ? C5 C4 C3 178.7(2) . . ? C4 C5 C6 175.4(2) . . ? C5 C6 C7 111.16(14) . . ? C5 C6 H6A 108.0(10) . . ? C7 C6 H6A 109.0(10) . . ? C5 C6 H6B 109.7(11) . . ? C7 C6 H6B 111.7(10) . . ? H6A C6 H6B 107.1(15) . . ? C8 C7 C6 112.93(15) . . ? C8 C7 H7A 111.0(10) . . ? C6 C7 H7A 108.5(10) . . ? C8 C7 H7B 107.9(10) . . ? C6 C7 H7B 108.0(10) . . ? H7A C7 H7B 108.4(15) . . ? C7 C8 C9 113.09(15) . . ? C7 C8 H8A 110.5(10) . . ? C9 C8 H8A 105.9(10) . . ? C7 C8 H8B 109.4(10) . . ? C9 C8 H8B 108.5(10) . . ? H8A C8 H8B 109.3(14) . . ? C10 C9 C8 111.61(13) . . ? C10 C9 H9A 110.2(11) . . ? C8 C9 H9A 109.2(12) . . ? C10 C9 H9B 109.5(11) . . ? C8 C9 H9B 109.7(11) . . ? H9A C9 H9B 106.5(16) . . ? C11 C10 C9 176.2(2) . . ? C10 C11 C12 178.7(2) . . ? C11 C12 Si1 113.84(11) . . ? C11 C12 H12A 111.0(11) . . ? Si1 C12 H12A 105.0(11) . . ? C11 C12 H12B 109.3(11) . . ? Si1 C12 H12B 107.6(10) . . ? H12A C12 H12B 109.9(16) . . ? Si1 C13 H13A 108.4(15) . . ? Si1 C13 H13B 113.1(15) . . ? H13A C13 H13B 103.3(20) . . ? Si1 C13 H13C 110.3(14) . . ? H13A C13 H13C 106.9(19) . . ? H13B C13 H13C 114.3(20) . . ? Si1 C14 H14A 111.4(15) . . ? Si1 C14 H14B 109.4(15) . . ? H14A C14 H14B 105.2(20) . . ? Si1 C14 H14C 111.4(15) . . ? H14A C14 H14C 109.1(20) . . ? H14B C14 H14C 110.1(20) . . ? Si2 C15 H15A 110.1(13) . . ? Si2 C15 H15B 110.3(14) . . ? H15A C15 H15B 110.3(19) . . ? Si2 C15 H15C 110.5(14) . . ? H15A C15 H15C 107.4(18) . . ? H15B C15 H15C 108.0(20) . . ? Si2 C16 H16A 110.0(14) . . ? Si2 C16 H16B 108.6(15) . . ? H16A C16 H16B 109.7(20) . . ? Si2 C16 H16C 109.1(15) . . ? H16A C16 H16C 109.5(20) . . ? H16B C16 H16C 109.8(21) . . ? _refine_diff_density_max 0.246 _refine_diff_density_min -0.217 _refine_diff_density_rms 0.037 #===END data_701GH170D _audit_creation_method SHELXL-97 _chemical_name_systematic ; 1,1,2,2-Tetramethyl-1,2-disilacyclotrideca-4,11-diyne (11) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C15 H26 Si2' _chemical_formula_weight 262.54 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting triclinic _symmetry_space_group_name_H-M P-1 loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, -y, -z' _cell_length_a 10.268(2) _cell_length_b 11.346(2) _cell_length_c 8.679(2) _cell_angle_alpha 111.72(3) _cell_angle_beta 113.95(3) _cell_angle_gamma 70.04(3) _cell_volume 836.4(3) _cell_formula_units_Z 2 _cell_measurement_temperature 253(2) _cell_measurement_reflns_used 75 _cell_measurement_theta_min 10.0 _cell_measurement_theta_max 20.3 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.45 _exptl_crystal_size_mid 0.40 _exptl_crystal_size_min 0.14 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.042 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 288 _exptl_absorpt_coefficient_mu 0.193 _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.918 _exptl_absorpt_correction_T_max 0.973 _exptl_special_details ; ? ; _diffrn_ambient_temperature 253(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type NONIUS_CAD4 _diffrn_measurement_method \w2\q _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_count 100 _diffrn_standards_interval_time 60 _diffrn_standards_decay_% 1.6 _diffrn_reflns_number 4290 _diffrn_reflns_av_R_equivalents 0.017 _diffrn_reflns_av_sigmaI/netI 0.017 _diffrn_reflns_limit_h_min -12 _diffrn_reflns_limit_h_max 13 _diffrn_reflns_limit_k_min -13 _diffrn_reflns_limit_k_max 14 _diffrn_reflns_limit_l_min -11 _diffrn_reflns_limit_l_max 0 _diffrn_reflns_theta_min 2.2 _diffrn_reflns_theta_max 28.0 _reflns_number_total 4028 _reflns_number_gt 3273 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0506P)^2^+0.1518P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment calculated _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 4028 _refine_ls_number_parameters 166 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.050 _refine_ls_R_factor_gt 0.037 _refine_ls_wR_factor_ref 0.107 _refine_ls_wR_factor_gt 0.100 _refine_ls_goodness_of_fit_ref 1.12 _refine_ls_restrained_S_all 1.12 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si1 Si -0.27738(5) 0.43316(4) 0.30726(6) 0.04564(13) Uani 1 d . . . Si2 Si -0.17370(4) 0.27784(4) 0.09522(5) 0.03984(11) Uani 1 d . . . C11 C -0.59409(18) 0.28557(17) 0.2116(2) 0.0546(4) Uani 1 d . . . C3 C -0.01617(15) 0.15218(14) 0.1949(2) 0.0444(3) Uani 1 d . . . H3A H 0.0417 0.1059 0.1166 0.053 Uiso 1 calc R . . H3B H 0.0461 0.1970 0.3043 0.053 Uiso 1 calc R . . C4 C -0.06105(15) 0.05728(14) 0.22865(19) 0.0427(3) Uani 1 d . . . C5 C -0.09927(17) -0.01890(15) 0.2553(2) 0.0464(3) Uani 1 d . . . C6 C -0.1484(2) -0.10857(16) 0.2951(2) 0.0568(4) Uani 1 d . . . H6A H -0.0655 -0.1550 0.3719 0.068 Uiso 1 calc R A 1 H6B H -0.1860 -0.1722 0.1874 0.068 Uiso 1 calc R A 1 C7 C -0.2662(2) -0.0383(2) 0.3816(3) 0.0472(4) Uani 0.75 d P B 1 H7A H -0.2295 0.0260 0.4888 0.057 Uiso 0.75 calc PR B 1 H7B H -0.2911 -0.1003 0.4117 0.057 Uiso 0.75 calc PR B 1 C8 C -0.4026(2) 0.02865(19) 0.2593(2) 0.0410(4) Uani 0.75 d P B 1 H8A H -0.4403 -0.0365 0.1539 0.049 Uiso 0.75 calc PR B 1 H8B H -0.3760 0.0876 0.2255 0.049 Uiso 0.75 calc PR B 1 C7A C -0.3278(9) -0.0591(8) 0.2656(12) 0.0655(18) Uiso 0.25 d P B 2 H7A1 H -0.3801 -0.0448 0.1503 0.079 Uiso 0.25 calc PR B 2 H7A2 H -0.3625 -0.1255 0.2735 0.079 Uiso 0.25 calc PR B 2 C8A C -0.3548(9) 0.0601(8) 0.3980(11) 0.0661(18) Uiso 0.25 d P B 2 H8A1 H -0.3116 0.1246 0.3997 0.079 Uiso 0.25 calc PR B 2 H8A2 H -0.3145 0.0447 0.5129 0.079 Uiso 0.25 calc PR B 2 C9 C -0.52413(19) 0.10602(18) 0.3446(2) 0.0575(4) Uani 1 d . . . H9A H -0.5631 0.0468 0.3619 0.069 Uiso 1 calc R C 1 H9B H -0.4849 0.1642 0.4576 0.069 Uiso 1 calc R C 1 C10 C -0.64231(19) 0.18261(19) 0.2237(2) 0.0588(4) Uani 1 d . . . H10A H -0.6729 0.1241 0.1079 0.071 Uiso 1 calc R . . H10B H -0.7262 0.2214 0.2652 0.071 Uiso 1 calc R . . C12 C -0.54676(17) 0.36826(17) 0.2135(2) 0.0530(4) Uani 1 d . . . C13 C -0.48435(18) 0.47036(17) 0.2268(3) 0.0592(4) Uani 1 d . . . H13A H -0.5200 0.5500 0.3058 0.071 Uiso 1 calc R . . H13B H -0.5190 0.4858 0.1125 0.071 Uiso 1 calc R . . C14 C -0.2144(2) 0.3823(2) 0.5113(2) 0.0705(5) Uani 1 d . . . H14A H -0.1096 0.3648 0.5571 0.106 Uiso 1 calc R . . H14B H -0.2467 0.3051 0.4859 0.106 Uiso 1 calc R . . H14C H -0.2545 0.4509 0.5963 0.106 Uiso 1 calc R . . C15 C -0.2294(3) 0.59133(18) 0.3565(3) 0.0848(7) Uani 1 d . . . H15A H -0.2753 0.6572 0.4382 0.127 Uiso 1 calc R . . H15B H -0.2631 0.6167 0.2502 0.127 Uiso 1 calc R . . H15C H -0.1252 0.5811 0.4062 0.127 Uiso 1 calc R . . C16 C -0.3081(2) 0.18952(18) -0.0917(2) 0.0628(5) Uani 1 d . . . H16A H -0.3875 0.2507 -0.1473 0.094 Uiso 1 calc R . . H16B H -0.3451 0.1446 -0.0495 0.094 Uiso 1 calc R . . H16C H -0.2610 0.1278 -0.1747 0.094 Uiso 1 calc R . . C17 C -0.0935(2) 0.36012(19) 0.0152(3) 0.0676(5) Uani 1 d . . . H17A H -0.0532 0.2974 -0.0733 0.101 Uiso 1 calc R . . H17B H -0.0177 0.3980 0.1111 0.101 Uiso 1 calc R . . H17C H -0.1685 0.4272 -0.0331 0.101 Uiso 1 calc R . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.0475(2) 0.0358(2) 0.0566(3) 0.00365(17) 0.02991(19) -0.00631(16) Si2 0.0440(2) 0.03461(19) 0.0446(2) 0.00548(15) 0.02251(16) -0.00872(15) C11 0.0487(8) 0.0625(10) 0.0559(9) 0.0112(8) 0.0253(7) -0.0113(7) C3 0.0390(7) 0.0434(7) 0.0516(8) 0.0070(6) 0.0218(6) -0.0076(6) C4 0.0385(7) 0.0423(7) 0.0434(7) 0.0087(6) 0.0174(6) -0.0024(5) C5 0.0471(8) 0.0432(7) 0.0492(8) 0.0127(6) 0.0217(6) -0.0027(6) C6 0.0663(10) 0.0440(8) 0.0699(11) 0.0241(8) 0.0323(9) -0.0014(7) C7 0.0558(11) 0.0499(11) 0.0450(11) 0.0210(9) 0.0201(9) -0.0085(9) C8 0.0466(10) 0.0479(10) 0.0336(8) 0.0091(7) 0.0176(7) -0.0129(8) C9 0.0539(9) 0.0608(10) 0.0676(10) 0.0133(8) 0.0273(8) -0.0194(8) C10 0.0567(9) 0.0742(11) 0.0537(9) 0.0064(8) 0.0240(8) -0.0285(9) C12 0.0420(8) 0.0578(9) 0.0641(10) 0.0203(8) 0.0268(7) -0.0006(7) C13 0.0506(9) 0.0530(9) 0.0864(13) 0.0314(9) 0.0354(9) 0.0041(7) C14 0.0697(12) 0.0785(13) 0.0548(10) 0.0121(9) 0.0308(9) 0.0003(10) C15 0.1037(17) 0.0445(9) 0.1161(18) -0.0154(11) 0.0680(15) -0.0290(10) C16 0.0629(10) 0.0527(9) 0.0541(10) 0.0065(7) 0.0073(8) -0.0135(8) C17 0.0822(13) 0.0610(10) 0.0858(13) 0.0238(10) 0.0530(11) -0.0105(9) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C14 1.860(2) . ? Si1 C15 1.8739(19) . ? Si1 C13 1.8929(18) . ? Si1 Si2 2.3527(11) . ? Si2 C16 1.8612(19) . ? Si2 C17 1.8708(17) . ? Si2 C3 1.8974(17) . ? C11 C12 1.188(2) . ? C11 C10 1.466(2) . ? C3 C4 1.463(2) . ? C3 H3A 0.9700 . ? C3 H3B 0.9700 . ? C4 C5 1.187(2) . ? C5 C6 1.470(2) . ? C6 C7 1.516(3) . ? C6 C7A 1.671(9) . ? C6 H6A 0.9700 . ? C6 H6B 0.9700 . ? C7 C8 1.526(3) . ? C7 H7A 0.9700 . ? C7 H7B 0.9700 . ? C8 C9 1.549(2) . ? C8 H8A 0.9700 . ? C8 H8B 0.9700 . ? C7A C8A 1.442(11) . ? C7A H7A1 0.9700 . ? C7A H7A2 0.9700 . ? C8A C9 1.555(8) . ? C8A H8A1 0.9700 . ? C8A H8A2 0.9700 . ? C9 C10 1.500(3) . ? C9 H9A 0.9700 . ? C9 H9B 0.9700 . ? C10 H10A 0.9700 . ? C10 H10B 0.9700 . ? C12 C13 1.454(2) . ? C13 H13A 0.9700 . ? C13 H13B 0.9700 . ? C14 H14A 0.9600 . ? C14 H14B 0.9600 . ? C14 H14C 0.9600 . ? C15 H15A 0.9600 . ? C15 H15B 0.9600 . ? C15 H15C 0.9600 . ? C16 H16A 0.9600 . ? C16 H16B 0.9600 . ? C16 H16C 0.9600 . ? C17 H17A 0.9600 . ? C17 H17B 0.9600 . ? C17 H17C 0.9600 . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C14 Si1 C15 110.37(12) . . ? C14 Si1 C13 107.47(9) . . ? C15 Si1 C13 104.93(10) . . ? C14 Si1 Si2 112.49(7) . . ? C15 Si1 Si2 108.29(7) . . ? C13 Si1 Si2 113.04(7) . . ? C16 Si2 C17 110.34(10) . . ? C16 Si2 C3 107.71(8) . . ? C17 Si2 C3 106.09(8) . . ? C16 Si2 Si1 112.54(7) . . ? C17 Si2 Si1 109.25(7) . . ? C3 Si2 Si1 110.71(6) . . ? C12 C11 C10 175.03(19) . . ? C4 C3 Si2 114.29(10) . . ? C4 C3 H3A 108.7 . . ? Si2 C3 H3A 108.7 . . ? C4 C3 H3B 108.7 . . ? Si2 C3 H3B 108.7 . . ? H3A C3 H3B 107.6 . . ? C5 C4 C3 179.16(15) . . ? C4 C5 C6 177.38(16) . . ? C5 C6 C7 112.30(14) . . ? C5 C6 C7A 110.3(3) . . ? C7 C6 C7A 33.8(3) . . ? C5 C6 H6A 109.1 . . ? C7 C6 H6A 109.1 . . ? C7A C6 H6A 134.8 . . ? C5 C6 H6B 109.1 . . ? C7 C6 H6B 109.1 . . ? C7A C6 H6B 78.9 . . ? H6A C6 H6B 107.9 . . ? C6 C7 C8 110.63(16) . . ? C6 C7 H7A 109.5 . . ? C8 C7 H7A 109.5 . . ? C6 C7 H7B 109.5 . . ? C8 C7 H7B 109.5 . . ? H7A C7 H7B 108.1 . . ? C7 C8 C9 112.51(15) . . ? C7 C8 H8A 109.1 . . ? C9 C8 H8A 109.1 . . ? C7 C8 H8B 109.1 . . ? C9 C8 H8B 109.1 . . ? H8A C8 H8B 107.8 . . ? C8A C7A C6 109.2(6) . . ? C8A C7A H7A1 109.8 . . ? C6 C7A H7A1 109.8 . . ? C8A C7A H7A2 109.8 . . ? C6 C7A H7A2 109.8 . . ? H7A1 C7A H7A2 108.3 . . ? C7A C8A C9 104.8(6) . . ? C7A C8A H8A1 110.8 . . ? C9 C8A H8A1 110.8 . . ? C7A C8A H8A2 110.8 . . ? C9 C8A H8A2 110.8 . . ? H8A1 C8A H8A2 108.9 . . ? C10 C9 C8 107.57(15) . . ? C10 C9 C8A 136.8(3) . . ? C8 C9 C8A 40.2(3) . . ? C10 C9 H9A 110.2 . . ? C8 C9 H9A 110.2 . . ? C8A C9 H9A 109.0 . . ? C10 C9 H9B 110.2 . . ? C8 C9 H9B 110.2 . . ? C8A C9 H9B 73.1 . . ? H9A C9 H9B 108.5 . . ? C11 C10 C9 112.29(14) . . ? C11 C10 H10A 109.1 . . ? C9 C10 H10A 109.1 . . ? C11 C10 H10B 109.1 . . ? C9 C10 H10B 109.1 . . ? H10A C10 H10B 107.9 . . ? C11 C12 C13 176.60(19) . . ? C12 C13 Si1 114.45(12) . . ? C12 C13 H13A 108.6 . . ? Si1 C13 H13A 108.6 . . ? C12 C13 H13B 108.6 . . ? Si1 C13 H13B 108.6 . . ? H13A C13 H13B 107.6 . . ? Si1 C14 H14A 109.5 . . ? Si1 C14 H14B 109.5 . . ? H14A C14 H14B 109.5 . . ? Si1 C14 H14C 109.5 . . ? H14A C14 H14C 109.5 . . ? H14B C14 H14C 109.5 . . ? Si1 C15 H15A 109.5 . . ? Si1 C15 H15B 109.5 . . ? H15A C15 H15B 109.5 . . ? Si1 C15 H15C 109.5 . . ? H15A C15 H15C 109.5 . . ? H15B C15 H15C 109.5 . . ? Si2 C16 H16A 109.5 . . ? Si2 C16 H16B 109.5 . . ? H16A C16 H16B 109.5 . . ? Si2 C16 H16C 109.5 . . ? H16A C16 H16C 109.5 . . ? H16B C16 H16C 109.5 . . ? Si2 C17 H17A 109.5 . . ? Si2 C17 H17B 109.5 . . ? H17A C17 H17B 109.5 . . ? Si2 C17 H17C 109.5 . . ? H17A C17 H17C 109.5 . . ? H17B C17 H17C 109.5 . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C14 Si1 Si2 C16 107.76(11) . . . . ? C15 Si1 Si2 C16 -130.00(12) . . . . ? C13 Si1 Si2 C16 -14.18(9) . . . . ? C14 Si1 Si2 C17 -129.31(11) . . . . ? C15 Si1 Si2 C17 -7.07(12) . . . . ? C13 Si1 Si2 C17 108.74(10) . . . . ? C14 Si1 Si2 C3 -12.84(9) . . . . ? C15 Si1 Si2 C3 109.41(11) . . . . ? C13 Si1 Si2 C3 -134.78(8) . . . . ? C16 Si2 C3 C4 -48.44(13) . . . . ? C17 Si2 C3 C4 -166.60(11) . . . . ? Si1 Si2 C3 C4 74.99(11) . . . . ? Si2 C3 C4 C5 -3(11) . . . . ? C3 C4 C5 C6 -70(12) . . . . ? C4 C5 C6 C7 28(4) . . . . ? C4 C5 C6 C7A 64(4) . . . . ? C5 C6 C7 C8 62.6(2) . . . . ? C7A C6 C7 C8 -30.9(5) . . . . ? C6 C7 C8 C9 -177.92(16) . . . . ? C5 C6 C7A C8A -68.6(7) . . . . ? C7 C6 C7A C8A 31.5(5) . . . . ? C6 C7A C8A C9 173.1(5) . . . . ? C7 C8 C9 C10 171.87(15) . . . . ? C7 C8 C9 C8A 27.9(5) . . . . ? C7A C8A C9 C10 -84.6(7) . . . . ? C7A C8A C9 C8 -29.7(4) . . . . ? C12 C11 C10 C9 -19(2) . . . . ? C8 C9 C10 C11 -67.46(19) . . . . ? C8A C9 C10 C11 -33.8(5) . . . . ? C10 C11 C12 C13 -19(4) . . . . ? C11 C12 C13 Si1 59(3) . . . . ? C14 Si1 C13 C12 -50.88(17) . . . . ? C15 Si1 C13 C12 -168.36(15) . . . . ? Si2 Si1 C13 C12 73.84(15) . . . . ? _diffrn_measured_fraction_theta_max 0.998 _diffrn_reflns_theta_full 28.0 _diffrn_measured_fraction_theta_full 0.998 _refine_diff_density_max 0.28 _refine_diff_density_min -0.19 _refine_diff_density_rms 0.04 #===END data_697GHP60B _audit_creation_method SHELXL-97 _chemical_name_systematic ; 1,1,2,2,6,6,7,7-Octamethyl-1,2,6,7-tetrasilacyclodeca- 3,9-diyne (12) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C14 H28 Si4' _chemical_formula_weight 308.7 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M 'P 2(1)/c' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 11.139(2) _cell_length_b 14.468(1) _cell_length_c 12.472(2) _cell_angle_alpha 90.00 _cell_angle_beta 97.34(2) _cell_angle_gamma 90.00 _cell_volume 1993.5(5) _cell_formula_units_Z 4 _cell_measurement_temperature 223(2) _cell_measurement_reflns_used 75 _cell_measurement_theta_min 10.0 _cell_measurement_theta_max 20.3 _exptl_crystal_description cube _exptl_crystal_colour colourless _exptl_crystal_size_max 0.45 _exptl_crystal_size_mid 0.40 _exptl_crystal_size_min 0.40 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.03 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 672 _exptl_absorpt_coefficient_mu 0.285 _exptl_absorpt_correction_type semiempirical _exptl_absorpt_correction_T_min 0.88 _exptl_absorpt_correction_T_max 0.99 _exptl_special_details ; ? ; _diffrn_ambient_temperature 223(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'NONIUS CAD4' _diffrn_measurement_method \w2\q _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_count 100 _diffrn_standards_interval_time 60 _diffrn_standards_decay_% -7.9 _diffrn_reflns_number 5018 _diffrn_reflns_av_R_equivalents 0.027 _diffrn_reflns_av_sigmaI/netI 0.019 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 14 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 19 _diffrn_reflns_limit_l_min -16 _diffrn_reflns_limit_l_max 16 _diffrn_reflns_theta_min 2.2 _diffrn_reflns_theta_max 28.0 _reflns_number_total 4782 _reflns_number_gt 3608 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0582P)^2^+0.1978P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 4782 _refine_ls_number_parameters 187 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.051 _refine_ls_R_factor_gt 0.032 _refine_ls_wR_factor_ref 0.099 _refine_ls_wR_factor_gt 0.086 _refine_ls_goodness_of_fit_ref 1.07 _refine_ls_restrained_S_all 1.07 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si1 Si 0.18685(4) 0.27090(3) 0.12137(3) 0.03993(11) Uani 1 d . . . Si2 Si 0.20439(3) 0.11155(3) 0.09631(3) 0.03650(11) Uani 1 d . . . Si6 Si 0.65738(3) 0.10966(2) 0.29480(3) 0.03243(10) Uani 1 d . . . Si7 Si 0.64679(3) 0.27077(2) 0.31339(3) 0.03218(10) Uani 1 d . . . C3 C 0.36615(13) 0.08642(10) 0.10940(11) 0.0394(3) Uani 1 d . . . C4 C 0.47362(13) 0.07795(9) 0.12534(10) 0.0361(3) Uani 1 d . . . C5 C 0.60418(13) 0.06935(11) 0.15206(12) 0.0379(3) Uani 1 d . . . H5A H 0.6431(17) 0.1051(13) 0.1067(14) 0.060(5) Uiso 1 d . . . H5B H 0.6293(16) 0.0078(13) 0.1453(14) 0.052(5) Uiso 1 d . . . C8 C 0.50642(14) 0.31175(11) 0.37080(13) 0.0426(3) Uani 1 d . . . H8A H 0.4967(16) 0.2767(13) 0.4306(15) 0.053(5) Uiso 1 d . . . H8B H 0.5191(16) 0.3739(13) 0.3911(14) 0.057(5) Uiso 1 d . . . C9 C 0.39678(13) 0.30561(9) 0.29394(11) 0.0384(3) Uani 1 d . . . C10 C 0.30965(13) 0.29978(10) 0.22746(12) 0.0407(3) Uani 1 d . . . C11 C 0.2045(2) 0.33587(14) -0.00475(14) 0.0692(5) Uani 1 d . . . H11A H 0.2006 0.4017 0.0091 0.104 Uiso 1 calc R . . H11B H 0.1399 0.3188 -0.0610 0.104 Uiso 1 calc R . . H11C H 0.2820 0.3209 -0.0280 0.104 Uiso 1 calc R . . C12 C 0.03767(16) 0.29942(14) 0.16752(18) 0.0644(5) Uani 1 d . . . H12A H 0.0316 0.2688 0.2358 0.097 Uiso 1 calc R . . H12B H -0.0274 0.2785 0.1139 0.097 Uiso 1 calc R . . H12C H 0.0315 0.3657 0.1768 0.097 Uiso 1 calc R . . C13 C 0.13177(14) 0.07603(12) -0.04059(12) 0.0480(4) Uani 1 d . . . H13A H 0.1734 0.1053 -0.0953 0.072 Uiso 1 calc R . . H13B H 0.0475 0.0949 -0.0500 0.072 Uiso 1 calc R . . H13C H 0.1367 0.0094 -0.0476 0.072 Uiso 1 calc R . . C14 C 0.13768(16) 0.04865(12) 0.20554(13) 0.0524(4) Uani 1 d . . . H14A H 0.1471 -0.0174 0.1963 0.079 Uiso 1 calc R . . H14B H 0.0523 0.0635 0.2016 0.079 Uiso 1 calc R . . H14C H 0.1790 0.0672 0.2754 0.079 Uiso 1 calc R . . C15 C 0.56659(18) 0.04905(12) 0.38843(13) 0.0563(4) Uani 1 d . . . H15A H 0.5750 -0.0172 0.3803 0.084 Uiso 1 calc R . . H15B H 0.4821 0.0661 0.3715 0.084 Uiso 1 calc R . . H15C H 0.5953 0.0666 0.4623 0.084 Uiso 1 calc R . . C16 C 0.82021(15) 0.07547(13) 0.32357(17) 0.0618(5) Uani 1 d . . . H16A H 0.8490 0.0870 0.3991 0.093 Uiso 1 calc R . . H16B H 0.8676 0.1114 0.2785 0.093 Uiso 1 calc R . . H16C H 0.8285 0.0103 0.3080 0.093 Uiso 1 calc R . . C17 C 0.77759(14) 0.30731(11) 0.41433(13) 0.0466(4) Uani 1 d . . . H17A H 0.8529 0.2938 0.3861 0.070 Uiso 1 calc R . . H17B H 0.7751 0.2739 0.4814 0.070 Uiso 1 calc R . . H17C H 0.7724 0.3732 0.4276 0.070 Uiso 1 calc R . . C18 C 0.65419(17) 0.33079(12) 0.18207(13) 0.0525(4) Uani 1 d . . . H18A H 0.6516 0.3971 0.1929 0.079 Uiso 1 calc R . . H18B H 0.5858 0.3121 0.1305 0.079 Uiso 1 calc R . . H18C H 0.7289 0.3144 0.1545 0.079 Uiso 1 calc R . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.0358(2) 0.0380(2) 0.0442(2) -0.00722(16) -0.00186(16) 0.00260(15) Si2 0.0324(2) 0.0377(2) 0.0387(2) -0.00669(15) 0.00176(15) -0.00012(14) Si6 0.03118(19) 0.02960(18) 0.03657(19) 0.00064(14) 0.00461(14) -0.00027(13) Si7 0.03264(19) 0.02974(19) 0.03339(18) -0.00038(13) 0.00123(14) -0.00094(13) C3 0.0379(7) 0.0391(7) 0.0408(7) -0.0045(6) 0.0031(6) 0.0023(6) C4 0.0410(7) 0.0331(6) 0.0343(6) -0.0051(5) 0.0049(5) -0.0002(5) C5 0.0338(7) 0.0403(7) 0.0412(7) -0.0057(6) 0.0108(5) 0.0005(6) C8 0.0405(8) 0.0458(8) 0.0405(7) -0.0120(6) 0.0008(6) 0.0052(6) C9 0.0367(7) 0.0357(7) 0.0435(7) -0.0080(6) 0.0069(6) 0.0036(5) C10 0.0378(7) 0.0379(7) 0.0460(7) -0.0072(6) 0.0037(6) 0.0013(6) C11 0.0986(16) 0.0541(10) 0.0521(10) 0.0038(8) -0.0013(10) -0.0002(10) C12 0.0373(8) 0.0661(11) 0.0881(14) -0.0258(10) 0.0019(8) 0.0054(8) C13 0.0448(8) 0.0525(9) 0.0444(8) -0.0089(7) -0.0033(6) -0.0017(7) C14 0.0539(9) 0.0549(9) 0.0507(9) -0.0052(7) 0.0159(7) -0.0027(8) C15 0.0762(12) 0.0486(9) 0.0472(9) 0.0034(7) 0.0201(8) -0.0148(8) C16 0.0410(9) 0.0540(10) 0.0863(13) -0.0073(9) -0.0076(8) 0.0131(7) C17 0.0402(8) 0.0488(9) 0.0483(8) -0.0031(7) -0.0043(6) -0.0084(6) C18 0.0667(11) 0.0475(8) 0.0433(8) 0.0097(7) 0.0074(7) -0.0018(8) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C10 1.8259(16) . ? Si1 C11 1.8642(19) . ? Si1 C12 1.8728(18) . ? Si1 Si2 2.3382(6) . ? Si2 C3 1.8249(15) . ? Si2 C13 1.8656(15) . ? Si2 C14 1.8694(17) . ? Si6 C15 1.8594(16) . ? Si6 C16 1.8700(16) . ? Si6 C5 1.8951(15) . ? Si6 Si7 2.3469(5) . ? Si7 C18 1.8650(15) . ? Si7 C17 1.8757(15) . ? Si7 C8 1.8960(16) . ? C3 C4 1.1944(19) . ? C4 C5 1.4552(19) . ? C5 H5A 0.916(18) . ? C5 H5B 0.940(19) . ? C8 C9 1.456(2) . ? C8 H8A 0.919(18) . ? C8 H8B 0.940(19) . ? C9 C10 1.196(2) . ? C11 H11A 0.9700 . ? C11 H11B 0.9700 . ? C11 H11C 0.9700 . ? C12 H12A 0.9700 . ? C12 H12B 0.9700 . ? C12 H12C 0.9700 . ? C13 H13A 0.9700 . ? C13 H13B 0.9700 . ? C13 H13C 0.9700 . ? C14 H14A 0.9700 . ? C14 H14B 0.9700 . ? C14 H14C 0.9700 . ? C15 H15A 0.9700 . ? C15 H15B 0.9700 . ? C15 H15C 0.9700 . ? C16 H16A 0.9700 . ? C16 H16B 0.9700 . ? C16 H16C 0.9700 . ? C17 H17A 0.9700 . ? C17 H17B 0.9700 . ? C17 H17C 0.9700 . ? C18 H18A 0.9700 . ? C18 H18B 0.9700 . ? C18 H18C 0.9700 . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C10 Si1 C11 110.26(9) . . ? C10 Si1 C12 109.81(8) . . ? C11 Si1 C12 109.96(10) . . ? C10 Si1 Si2 104.77(5) . . ? C11 Si1 Si2 111.39(7) . . ? C12 Si1 Si2 110.54(6) . . ? C3 Si2 C13 109.56(7) . . ? C3 Si2 C14 108.52(8) . . ? C13 Si2 C14 111.51(8) . . ? C3 Si2 Si1 106.43(5) . . ? C13 Si2 Si1 111.10(6) . . ? C14 Si2 Si1 109.56(6) . . ? C15 Si6 C16 110.29(9) . . ? C15 Si6 C5 108.36(7) . . ? C16 Si6 C5 106.15(8) . . ? C15 Si6 Si7 111.60(6) . . ? C16 Si6 Si7 107.67(6) . . ? C5 Si6 Si7 112.63(5) . . ? C18 Si7 C17 109.91(8) . . ? C18 Si7 C8 108.49(8) . . ? C17 Si7 C8 105.41(7) . . ? C18 Si7 Si6 111.55(6) . . ? C17 Si7 Si6 107.56(5) . . ? C8 Si7 Si6 113.71(6) . . ? C4 C3 Si2 172.93(13) . . ? C3 C4 C5 176.27(14) . . ? C4 C5 Si6 111.85(10) . . ? C4 C5 H5A 110.4(11) . . ? Si6 C5 H5A 106.9(11) . . ? C4 C5 H5B 111.1(11) . . ? Si6 C5 H5B 108.4(10) . . ? H5A C5 H5B 108.0(16) . . ? C9 C8 Si7 113.28(10) . . ? C9 C8 H8A 108.9(12) . . ? Si7 C8 H8A 108.8(11) . . ? C9 C8 H8B 108.7(11) . . ? Si7 C8 H8B 107.3(11) . . ? H8A C8 H8B 109.8(15) . . ? C10 C9 C8 177.26(15) . . ? C9 C10 Si1 169.99(13) . . ? Si1 C11 H11A 109.5 . . ? Si1 C11 H11B 109.5 . . ? H11A C11 H11B 109.5 . . ? Si1 C11 H11C 109.5 . . ? H11A C11 H11C 109.5 . . ? H11B C11 H11C 109.5 . . ? Si1 C12 H12A 109.5 . . ? Si1 C12 H12B 109.5 . . ? H12A C12 H12B 109.5 . . ? Si1 C12 H12C 109.5 . . ? H12A C12 H12C 109.5 . . ? H12B C12 H12C 109.5 . . ? Si2 C13 H13A 109.5 . . ? Si2 C13 H13B 109.5 . . ? H13A C13 H13B 109.5 . . ? Si2 C13 H13C 109.5 . . ? H13A C13 H13C 109.5 . . ? H13B C13 H13C 109.5 . . ? Si2 C14 H14A 109.5 . . ? Si2 C14 H14B 109.5 . . ? H14A C14 H14B 109.5 . . ? Si2 C14 H14C 109.5 . . ? H14A C14 H14C 109.5 . . ? H14B C14 H14C 109.5 . . ? Si6 C15 H15A 109.5 . . ? Si6 C15 H15B 109.5 . . ? H15A C15 H15B 109.5 . . ? Si6 C15 H15C 109.5 . . ? H15A C15 H15C 109.5 . . ? H15B C15 H15C 109.5 . . ? Si6 C16 H16A 109.5 . . ? Si6 C16 H16B 109.5 . . ? H16A C16 H16B 109.5 . . ? Si6 C16 H16C 109.5 . . ? H16A C16 H16C 109.5 . . ? H16B C16 H16C 109.5 . . ? Si7 C17 H17A 109.5 . . ? Si7 C17 H17B 109.5 . . ? H17A C17 H17B 109.5 . . ? Si7 C17 H17C 109.5 . . ? H17A C17 H17C 109.5 . . ? H17B C17 H17C 109.5 . . ? Si7 C18 H18A 109.5 . . ? Si7 C18 H18B 109.5 . . ? H18A C18 H18B 109.5 . . ? Si7 C18 H18C 109.5 . . ? H18A C18 H18C 109.5 . . ? H18B C18 H18C 109.5 . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C10 Si1 Si2 C3 -37.98(7) . . . . ? C11 Si1 Si2 C3 81.21(9) . . . . ? C12 Si1 Si2 C3 -156.21(9) . . . . ? C10 Si1 Si2 C13 -157.19(8) . . . . ? C11 Si1 Si2 C13 -37.99(10) . . . . ? C12 Si1 Si2 C13 84.59(10) . . . . ? C10 Si1 Si2 C14 79.16(8) . . . . ? C11 Si1 Si2 C14 -161.64(10) . . . . ? C12 Si1 Si2 C14 -39.07(10) . . . . ? C15 Si6 Si7 C18 -146.92(9) . . . . ? C16 Si6 Si7 C18 91.91(10) . . . . ? C5 Si6 Si7 C18 -24.77(8) . . . . ? C15 Si6 Si7 C17 92.49(9) . . . . ? C16 Si6 Si7 C17 -28.68(9) . . . . ? C5 Si6 Si7 C17 -145.36(7) . . . . ? C15 Si6 Si7 C8 -23.83(9) . . . . ? C16 Si6 Si7 C8 -145.00(9) . . . . ? C5 Si6 Si7 C8 98.32(7) . . . . ? C13 Si2 C3 C4 149.7(11) . . . . ? C14 Si2 C3 C4 -88.3(11) . . . . ? Si1 Si2 C3 C4 29.5(11) . . . . ? Si2 C3 C4 C5 38(3) . . . . ? C3 C4 C5 Si6 -6(2) . . . . ? C15 Si6 C5 C4 52.11(13) . . . . ? C16 Si6 C5 C4 170.57(11) . . . . ? Si7 Si6 C5 C4 -71.85(11) . . . . ? C18 Si7 C8 C9 51.04(14) . . . . ? C17 Si7 C8 C9 168.73(11) . . . . ? Si6 Si7 C8 C9 -73.70(12) . . . . ? Si7 C8 C9 C10 -10(3) . . . . ? C8 C9 C10 Si1 56(4) . . . . ? C11 Si1 C10 C9 -105.9(8) . . . . ? C12 Si1 C10 C9 132.8(8) . . . . ? Si2 Si1 C10 C9 14.0(8) . . . . ? _diffrn_measured_fraction_theta_max 0.959 _diffrn_reflns_theta_full 28.0 _diffrn_measured_fraction_theta_full 0.959 _refine_diff_density_max 0.325 _refine_diff_density_min -0.214 _refine_diff_density_rms 0.045 #===END data_711GH164 _audit_creation_method SHELXL-97 _chemical_name_systematic ; 1,1,2,2,6,6,8,8-Octamethyl-1,2,6,8-tetrasilacycloundeca- 4,9-diyne (13) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C15 H30 Si4' _chemical_formula_weight 322.8 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting triclinic _symmetry_space_group_name_H-M 'P -1' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, -y, -z' _cell_length_a 11.725(2) _cell_length_b 12.678(1) _cell_length_c 8.391(1) _cell_angle_alpha 92.44(1) _cell_angle_beta 110.73(1) _cell_angle_gamma 65.26(1) _cell_volume 1051.3(2) _cell_formula_units_Z 2 _cell_measurement_temperature 223(2) _cell_measurement_reflns_used 75 _cell_measurement_theta_min 10.1 _cell_measurement_theta_max 23.7 _exptl_crystal_description irregular _exptl_crystal_colour colourless _exptl_crystal_size_max 0.45 _exptl_crystal_size_mid 0.45 _exptl_crystal_size_min 0.35 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.02 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 352 _exptl_absorpt_coefficient_mu 0.27 _exptl_absorpt_correction_type ? _exptl_absorpt_correction_T_min 0.964 _exptl_absorpt_correction_T_max 1.0 _exptl_special_details ; ? ; _diffrn_ambient_temperature 223(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type NONIUS_CAD4 _diffrn_measurement_method \w2\q _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_count 100 _diffrn_standards_interval_time 60 _diffrn_standards_decay_% -3.9 _diffrn_reflns_number 5268 _diffrn_reflns_av_R_equivalents 0.011 _diffrn_reflns_av_sigmaI/netI 0.013 _diffrn_reflns_limit_h_min -14 _diffrn_reflns_limit_h_max 15 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 16 _diffrn_reflns_limit_l_min -11 _diffrn_reflns_limit_l_max 11 _diffrn_reflns_theta_min 2.1 _diffrn_reflns_theta_max 28.0 _reflns_number_total 5042 _reflns_number_gt 4262 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0461P)^2^+0.1624P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 5042 _refine_ls_number_parameters 204 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.038 _refine_ls_R_factor_gt 0.029 _refine_ls_wR_factor_ref 0.087 _refine_ls_wR_factor_gt 0.080 _refine_ls_goodness_of_fit_ref 1.06 _refine_ls_restrained_S_all 1.06 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si1 Si 0.00899(3) 0.72673(3) 0.53477(5) 0.04377(10) Uani 1 d . . . Si2 Si -0.12518(4) 0.78124(4) 0.24077(5) 0.04843(10) Uani 1 d . . . Si6 Si 0.35189(4) 0.67768(3) 0.18450(4) 0.04768(10) Uani 1 d . . . Si8 Si 0.40331(3) 0.81824(3) 0.51097(4) 0.03842(9) Uani 1 d . . . C3 C -0.07947(15) 0.87553(14) 0.1303(2) 0.0563(3) Uani 1 d . . . H3A H -0.140(2) 0.8953(16) 0.017(3) 0.076(5) Uiso 1 d . . . H3B H -0.0947(18) 0.9461(16) 0.174(2) 0.067(5) Uiso 1 d . . . C4 C 0.05768(14) 0.81655(12) 0.13338(16) 0.0490(3) Uani 1 d . . . C5 C 0.17252(14) 0.76330(13) 0.14343(16) 0.0514(3) Uani 1 d . . . C7 C 0.45095(14) 0.67885(12) 0.41318(16) 0.0463(3) Uani 1 d . . . H7A H 0.539(2) 0.6530(16) 0.423(2) 0.076(6) Uiso 1 d . . . H7B H 0.4472(18) 0.6246(16) 0.476(2) 0.069(5) Uiso 1 d . . . C9 C 0.25697(12) 0.84303(11) 0.56492(15) 0.0409(2) Uani 1 d . . . C10 C 0.16308(12) 0.85056(10) 0.59898(14) 0.0383(2) Uani 1 d . . . C11 C 0.05256(13) 0.84779(12) 0.63725(16) 0.0422(3) Uani 1 d . . . H11A H -0.0271(16) 0.9233(14) 0.599(2) 0.054(4) Uiso 1 d . . . H11B H 0.0769(16) 0.8319(13) 0.760(2) 0.054(4) Uiso 1 d . . . C12 C -0.08863(19) 0.69912(17) 0.6501(2) 0.0700(4) Uani 1 d . . . H12A H -0.1213 0.6430 0.5953 0.105 Uiso 1 calc R . . H12B H -0.1648 0.7719 0.6459 0.105 Uiso 1 calc R . . H12C H -0.0303 0.6682 0.7689 0.105 Uiso 1 calc R . . C13 C 0.16948(16) 0.59270(13) 0.5702(2) 0.0629(4) Uani 1 d . . . H13A H 0.2236 0.5730 0.6921 0.094 Uiso 1 calc R . . H13B H 0.2196 0.6073 0.5103 0.094 Uiso 1 calc R . . H13C H 0.1486 0.5282 0.5267 0.094 Uiso 1 calc R . . C14 C -0.30568(15) 0.8716(2) 0.2139(3) 0.0822(6) Uani 1 d . . . H14A H -0.3613 0.8928 0.0926 0.123 Uiso 1 calc R . . H14B H -0.3137 0.9420 0.2685 0.123 Uiso 1 calc R . . H14C H -0.3356 0.8268 0.2668 0.123 Uiso 1 calc R . . C15 C -0.1073(2) 0.64740(16) 0.1300(2) 0.0726(5) Uani 1 d . . . H15A H -0.1343 0.5994 0.1818 0.109 Uiso 1 calc R . . H15B H -0.0138 0.6031 0.1414 0.109 Uiso 1 calc R . . H15C H -0.1644 0.6702 0.0093 0.109 Uiso 1 calc R . . C16 C 0.40443(18) 0.74019(17) 0.0417(2) 0.0671(4) Uani 1 d . . . H16A H 0.3586 0.7329 -0.0767 0.101 Uiso 1 calc R . . H16B H 0.5014 0.6981 0.0723 0.101 Uiso 1 calc R . . H16C H 0.3807 0.8222 0.0551 0.101 Uiso 1 calc R . . C17 C 0.3783(2) 0.52546(16) 0.1421(2) 0.0747(5) Uani 1 d . . . H17A H 0.3466 0.4949 0.2132 0.112 Uiso 1 calc R . . H17B H 0.4738 0.4766 0.1690 0.112 Uiso 1 calc R . . H17C H 0.3282 0.5256 0.0220 0.112 Uiso 1 calc R . . C18 C 0.35730(16) 0.94658(13) 0.3621(2) 0.0578(3) Uani 1 d . . . H18A H 0.2775 0.9577 0.2625 0.087 Uiso 1 calc R . . H18B H 0.4317 0.9330 0.3258 0.087 Uiso 1 calc R . . H18C H 0.3388 1.0160 0.4205 0.087 Uiso 1 calc R . . C19 C 0.54583(13) 0.80440(13) 0.71326(18) 0.0516(3) Uani 1 d . . . H19A H 0.5202 0.8759 0.7661 0.077 Uiso 1 calc R . . H19B H 0.6248 0.7910 0.6873 0.077 Uiso 1 calc R . . H19C H 0.5667 0.7391 0.7917 0.077 Uiso 1 calc R . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.04108(18) 0.0506(2) 0.04665(19) -0.00743(15) 0.01908(14) -0.02402(15) Si2 0.03719(17) 0.0616(2) 0.04615(19) -0.01525(16) 0.01426(14) -0.02269(16) Si6 0.0493(2) 0.0562(2) 0.03408(17) -0.00519(14) 0.01785(15) -0.01762(16) Si8 0.03645(16) 0.04558(18) 0.03580(16) -0.00056(12) 0.01458(13) -0.01864(13) C3 0.0455(7) 0.0568(8) 0.0521(8) 0.0022(6) 0.0110(6) -0.0139(6) C4 0.0504(7) 0.0582(8) 0.0335(6) 0.0014(5) 0.0101(5) -0.0229(6) C5 0.0512(7) 0.0660(8) 0.0338(6) -0.0018(5) 0.0128(5) -0.0242(6) C7 0.0429(6) 0.0498(7) 0.0366(6) -0.0005(5) 0.0141(5) -0.0114(5) C9 0.0407(6) 0.0486(6) 0.0364(5) -0.0049(5) 0.0149(5) -0.0214(5) C10 0.0392(6) 0.0444(6) 0.0323(5) -0.0056(4) 0.0121(4) -0.0198(5) C11 0.0398(6) 0.0518(7) 0.0407(6) -0.0087(5) 0.0190(5) -0.0220(5) C12 0.0767(11) 0.0802(11) 0.0839(11) -0.0129(9) 0.0456(9) -0.0492(9) C13 0.0572(8) 0.0523(8) 0.0708(10) -0.0076(7) 0.0215(7) -0.0177(7) C14 0.0389(7) 0.1219(16) 0.0738(11) -0.0301(11) 0.0181(7) -0.0277(9) C15 0.0834(12) 0.0732(11) 0.0630(10) -0.0235(8) 0.0225(9) -0.0407(9) C16 0.0677(10) 0.0920(12) 0.0457(8) -0.0031(8) 0.0300(7) -0.0304(9) C17 0.0916(13) 0.0665(10) 0.0576(9) -0.0197(8) 0.0256(9) -0.0292(9) C18 0.0654(9) 0.0542(8) 0.0592(8) 0.0042(6) 0.0286(7) -0.0253(7) C19 0.0435(6) 0.0655(8) 0.0494(7) -0.0059(6) 0.0136(6) -0.0297(6) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C13 1.8674(16) . ? Si1 C12 1.8756(15) . ? Si1 C11 1.8945(13) . ? Si1 Si2 2.3507(7) . ? Si2 C15 1.8689(17) . ? Si2 C14 1.8702(17) . ? Si2 C3 1.8864(17) . ? Si6 C5 1.8243(15) . ? Si6 C16 1.8588(15) . ? Si6 C7 1.8615(14) . ? Si6 C17 1.8618(18) . ? Si8 C9 1.8260(12) . ? Si8 C18 1.8599(14) . ? Si8 C19 1.8645(14) . ? Si8 C7 1.8663(14) . ? C3 C4 1.453(2) . ? C3 H3A 0.93(2) . ? C3 H3B 0.924(18) . ? C4 C5 1.200(2) . ? C7 H7A 0.92(2) . ? C7 H7B 0.908(19) . ? C9 C10 1.1980(17) . ? C10 C11 1.4550(16) . ? C11 H11A 0.979(16) . ? C11 H11B 0.971(16) . ? C12 H12A 0.9700 . ? C12 H12B 0.9700 . ? C12 H12C 0.9700 . ? C13 H13A 0.9700 . ? C13 H13B 0.9700 . ? C13 H13C 0.9700 . ? C14 H14A 0.9700 . ? C14 H14B 0.9700 . ? C14 H14C 0.9700 . ? C15 H15A 0.9700 . ? C15 H15B 0.9700 . ? C15 H15C 0.9700 . ? C16 H16A 0.9700 . ? C16 H16B 0.9700 . ? C16 H16C 0.9700 . ? C17 H17A 0.9700 . ? C17 H17B 0.9700 . ? C17 H17C 0.9700 . ? C18 H18A 0.9700 . ? C18 H18B 0.9700 . ? C18 H18C 0.9700 . ? C19 H19A 0.9700 . ? C19 H19B 0.9700 . ? C19 H19C 0.9700 . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C13 Si1 C12 109.73(8) . . ? C13 Si1 C11 108.61(7) . . ? C12 Si1 C11 105.95(7) . . ? C13 Si1 Si2 111.15(6) . . ? C12 Si1 Si2 109.28(6) . . ? C11 Si1 Si2 111.97(5) . . ? C15 Si2 C14 110.54(9) . . ? C15 Si2 C3 108.24(8) . . ? C14 Si2 C3 105.67(9) . . ? C15 Si2 Si1 109.73(6) . . ? C14 Si2 Si1 109.45(6) . . ? C3 Si2 Si1 113.15(5) . . ? C5 Si6 C16 110.54(7) . . ? C5 Si6 C7 108.75(6) . . ? C16 Si6 C7 109.81(8) . . ? C5 Si6 C17 107.53(9) . . ? C16 Si6 C17 110.03(9) . . ? C7 Si6 C17 110.15(8) . . ? C9 Si8 C18 108.08(7) . . ? C9 Si8 C19 108.22(6) . . ? C18 Si8 C19 110.13(7) . . ? C9 Si8 C7 108.57(6) . . ? C18 Si8 C7 112.35(7) . . ? C19 Si8 C7 109.39(7) . . ? C4 C3 Si2 113.04(11) . . ? C4 C3 H3A 109.4(12) . . ? Si2 C3 H3A 106.7(12) . . ? C4 C3 H3B 111.2(11) . . ? Si2 C3 H3B 111.2(11) . . ? H3A C3 H3B 104.9(15) . . ? C5 C4 C3 176.24(14) . . ? C4 C5 Si6 173.47(12) . . ? Si6 C7 Si8 119.38(7) . . ? Si6 C7 H7A 106.6(11) . . ? Si8 C7 H7A 107.9(11) . . ? Si6 C7 H7B 106.6(11) . . ? Si8 C7 H7B 108.2(11) . . ? H7A C7 H7B 107.6(16) . . ? C10 C9 Si8 175.03(11) . . ? C9 C10 C11 174.37(13) . . ? C10 C11 Si1 110.45(8) . . ? C10 C11 H11A 111.3(9) . . ? Si1 C11 H11A 110.6(9) . . ? C10 C11 H11B 111.5(9) . . ? Si1 C11 H11B 106.7(9) . . ? H11A C11 H11B 106.2(13) . . ? Si1 C12 H12A 109.5 . . ? Si1 C12 H12B 109.5 . . ? H12A C12 H12B 109.5 . . ? Si1 C12 H12C 109.5 . . ? H12A C12 H12C 109.5 . . ? H12B C12 H12C 109.5 . . ? Si1 C13 H13A 109.5 . . ? Si1 C13 H13B 109.5 . . ? H13A C13 H13B 109.5 . . ? Si1 C13 H13C 109.5 . . ? H13A C13 H13C 109.5 . . ? H13B C13 H13C 109.5 . . ? Si2 C14 H14A 109.5 . . ? Si2 C14 H14B 109.5 . . ? H14A C14 H14B 109.5 . . ? Si2 C14 H14C 109.5 . . ? H14A C14 H14C 109.5 . . ? H14B C14 H14C 109.5 . . ? Si2 C15 H15A 109.5 . . ? Si2 C15 H15B 109.5 . . ? H15A C15 H15B 109.5 . . ? Si2 C15 H15C 109.5 . . ? H15A C15 H15C 109.5 . . ? H15B C15 H15C 109.5 . . ? Si6 C16 H16A 109.5 . . ? Si6 C16 H16B 109.5 . . ? H16A C16 H16B 109.5 . . ? Si6 C16 H16C 109.5 . . ? H16A C16 H16C 109.5 . . ? H16B C16 H16C 109.5 . . ? Si6 C17 H17A 109.5 . . ? Si6 C17 H17B 109.5 . . ? H17A C17 H17B 109.5 . . ? Si6 C17 H17C 109.5 . . ? H17A C17 H17C 109.5 . . ? H17B C17 H17C 109.5 . . ? Si8 C18 H18A 109.5 . . ? Si8 C18 H18B 109.5 . . ? H18A C18 H18B 109.5 . . ? Si8 C18 H18C 109.5 . . ? H18A C18 H18C 109.5 . . ? H18B C18 H18C 109.5 . . ? Si8 C19 H19A 109.5 . . ? Si8 C19 H19B 109.5 . . ? H19A C19 H19B 109.5 . . ? Si8 C19 H19C 109.5 . . ? H19A C19 H19C 109.5 . . ? H19B C19 H19C 109.5 . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C13 Si1 Si2 C15 35.56(9) . . . . ? C12 Si1 Si2 C15 -85.70(9) . . . . ? C11 Si1 Si2 C15 157.23(8) . . . . ? C13 Si1 Si2 C14 157.02(10) . . . . ? C12 Si1 Si2 C14 35.76(10) . . . . ? C11 Si1 Si2 C14 -81.31(9) . . . . ? C13 Si1 Si2 C3 -85.44(8) . . . . ? C12 Si1 Si2 C3 153.31(8) . . . . ? C11 Si1 Si2 C3 36.24(7) . . . . ? C15 Si2 C3 C4 -59.44(13) . . . . ? C14 Si2 C3 C4 -177.87(11) . . . . ? Si1 Si2 C3 C4 62.39(12) . . . . ? Si2 C3 C4 C5 -18(2) . . . . ? C3 C4 C5 Si6 -29(3) . . . . ? C16 Si6 C5 C4 -149.1(12) . . . . ? C7 Si6 C5 C4 -28.5(12) . . . . ? C17 Si6 C5 C4 90.8(12) . . . . ? C5 Si6 C7 Si8 -42.58(11) . . . . ? C16 Si6 C7 Si8 78.49(11) . . . . ? C17 Si6 C7 Si8 -160.18(10) . . . . ? C9 Si8 C7 Si6 78.59(10) . . . . ? C18 Si8 C7 Si6 -40.89(11) . . . . ? C19 Si8 C7 Si6 -163.51(8) . . . . ? C18 Si8 C9 C10 138.1(12) . . . . ? C19 Si8 C9 C10 -102.6(12) . . . . ? C7 Si8 C9 C10 16.0(12) . . . . ? Si8 C9 C10 C11 -3(2) . . . . ? C9 C10 C11 Si1 -21.9(13) . . . . ? C13 Si1 C11 C10 43.64(11) . . . . ? C12 Si1 C11 C10 161.47(10) . . . . ? Si2 Si1 C11 C10 -79.48(9) . . . . ? _diffrn_measured_fraction_theta_max 0.999 _diffrn_reflns_theta_full 28.0 _diffrn_measured_fraction_theta_full 0.999 _refine_diff_density_max 0.25 _refine_diff_density_min -0.30 _refine_diff_density_rms 0.05 #===END data_718GH150D _audit_creation_method SHELXL-97 _chemical_name_systematic ; 1,1,2,2,6,6,9,9-Octamethyl-1,2,6,9-tetrasila- cyclododeca-4,10-diyne (14) ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C16 H32 Si4' _chemical_formula_weight 336.8 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source 'C' 'C' 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'H' 'H' 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'Si' 'Si' 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M 'P 2(1)/c' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 8.331(1) _cell_length_b 21.336(5) _cell_length_c 12.510(2) _cell_angle_alpha 90.0 _cell_angle_beta 100.58(1) _cell_angle_gamma 90.0 _cell_volume 2185.9(7) _cell_formula_units_Z 4 _cell_measurement_temperature 223(2) _cell_measurement_reflns_used 75 _cell_measurement_theta_min 10.0 _cell_measurement_theta_max 22.3 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.48 _exptl_crystal_size_mid 0.48 _exptl_crystal_size_min 0.25 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.023 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 736 _exptl_absorpt_coefficient_mu 0.26 _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.974 _exptl_absorpt_correction_T_max 0.998 _exptl_special_details ; ? ; _diffrn_ambient_temperature 223(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type NONIUS_CAD4 _diffrn_measurement_method \w2\q _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_count 100 _diffrn_standards_interval_time 60 _diffrn_standards_decay_% -0.9 _diffrn_reflns_number 5593 _diffrn_reflns_av_R_equivalents 0.024 _diffrn_reflns_av_sigmaI/netI 0.019 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 10 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 28 _diffrn_reflns_limit_l_min -16 _diffrn_reflns_limit_l_max 16 _diffrn_reflns_theta_min 2.5 _diffrn_reflns_theta_max 28.0 _reflns_number_total 5249 _reflns_number_gt 4245 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution 'SHELXS-97 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ? _computing_publication_material ? _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0432P)^2^+0.3701P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 5249 _refine_ls_number_parameters 285 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.044 _refine_ls_R_factor_gt 0.029 _refine_ls_wR_factor_ref 0.084 _refine_ls_wR_factor_gt 0.074 _refine_ls_goodness_of_fit_ref 1.07 _refine_ls_restrained_S_all 1.07 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group Si1 Si 0.33699(4) 0.559038(15) 0.72810(3) 0.03128(9) Uani 1 d . . . Si2 Si 0.11751(4) 0.508776(17) 0.78607(3) 0.03272(9) Uani 1 d . . . Si6 Si 0.22361(5) 0.322884(19) 0.52960(3) 0.04392(11) Uani 1 d . . . Si9 Si 0.63548(4) 0.341812(17) 0.82335(3) 0.03843(10) Uani 1 d . . . C3 C -0.03290(16) 0.48029(7) 0.66262(11) 0.0384(3) Uani 1 d . . . H3A H -0.131(2) 0.4680(8) 0.6876(13) 0.050(4) Uiso 1 d . . . H3B H -0.0577(19) 0.5145(8) 0.6175(13) 0.042(4) Uiso 1 d . . . C4 C 0.03551(16) 0.42832(6) 0.61059(10) 0.0372(3) Uani 1 d . . . C5 C 0.10110(17) 0.38557(7) 0.57396(11) 0.0416(3) Uani 1 d . . . C7 C 0.43407(18) 0.33117(7) 0.61076(12) 0.0440(3) Uani 1 d . . . H7A H 0.509(3) 0.3076(9) 0.5789(16) 0.071(6) Uiso 1 d . . . H7B H 0.465(2) 0.3744(9) 0.6044(14) 0.057(5) Uiso 1 d . . . C8 C 0.44925(18) 0.31233(7) 0.73076(12) 0.0414(3) Uani 1 d . . . H8A H 0.452(2) 0.2682(9) 0.7349(14) 0.053(5) Uiso 1 d . . . H8B H 0.357(2) 0.3274(8) 0.7546(14) 0.053(5) Uiso 1 d . . . C10 C 0.61494(17) 0.42717(7) 0.83169(12) 0.0433(3) Uani 1 d . . . C11 C 0.58137(16) 0.48154(6) 0.83592(11) 0.0400(3) Uani 1 d . . . C12 C 0.52841(18) 0.54668(6) 0.83471(13) 0.0431(3) Uani 1 d . . . H12A H 0.611(2) 0.5745(9) 0.8201(14) 0.060(5) Uiso 1 d . . . H12B H 0.508(2) 0.5574(8) 0.9050(16) 0.061(5) Uiso 1 d . . . C13 C 0.2978(2) 0.64534(7) 0.71656(16) 0.0533(4) Uani 1 d . . . H13A H 0.390(3) 0.6650(10) 0.6983(18) 0.080 Uiso 1 d . . . H13B H 0.282(3) 0.6637(10) 0.7823(18) 0.080 Uiso 1 d . . . H13C H 0.209(3) 0.6532(10) 0.6595(18) 0.080 Uiso 1 d . . . C14 C 0.3780(2) 0.53061(9) 0.59548(13) 0.0504(4) Uani 1 d . . . H14A H 0.292(3) 0.5409(10) 0.5399(17) 0.076 Uiso 1 d . . . H14B H 0.394(3) 0.4874(11) 0.5934(16) 0.076 Uiso 1 d . . . H14C H 0.470(3) 0.5506(10) 0.5779(16) 0.076 Uiso 1 d . . . C15 C 0.0111(2) 0.56503(9) 0.86354(15) 0.0537(4) Uani 1 d . . . H15A H -0.079(3) 0.5459(10) 0.8810(18) 0.080 Uiso 1 d . . . H15B H -0.020(3) 0.6016(11) 0.8232(18) 0.080 Uiso 1 d . . . H15C H 0.086(3) 0.5752(10) 0.9287(18) 0.080 Uiso 1 d . . . C16 C 0.1824(2) 0.44049(8) 0.87624(12) 0.0477(3) Uani 1 d . . . H16A H 0.252(3) 0.4532(10) 0.9336(18) 0.072 Uiso 1 d . . . H16B H 0.232(2) 0.4093(10) 0.8428(17) 0.072 Uiso 1 d . . . H16C H 0.089(2) 0.4249(9) 0.9048(16) 0.072 Uiso 1 d . . . C17 C 0.2261(3) 0.33262(13) 0.38223(15) 0.0723(6) Uani 1 d . . . H17A H 0.121(4) 0.3279(12) 0.340(2) 0.108 Uiso 1 d . . . H17B H 0.297(3) 0.3038(12) 0.363(2) 0.108 Uiso 1 d . . . H17C H 0.265(3) 0.3743(13) 0.368(2) 0.108 Uiso 1 d . . . C18 C 0.1345(3) 0.24572(10) 0.5548(2) 0.0776(6) Uani 1 d . . . H18A H 0.124(4) 0.2406(13) 0.625(2) 0.116 Uiso 1 d . . . H18B H 0.200(3) 0.2134(15) 0.537(2) 0.116 Uiso 1 d . . . H18C H 0.033(4) 0.2420(12) 0.513(2) 0.116 Uiso 1 d . . . C19 C 0.6442(3) 0.30887(9) 0.96163(15) 0.0590(4) Uani 1 d . . . H19A H 0.738(3) 0.3249(11) 1.0127(19) 0.089 Uiso 1 d . . . H19B H 0.654(3) 0.2650(12) 0.9575(18) 0.089 Uiso 1 d . . . H19C H 0.547(3) 0.3201(11) 0.9840(19) 0.089 Uiso 1 d . . . C20 C 0.8220(2) 0.32085(8) 0.77014(18) 0.0565(4) Uani 1 d . . . H20A H 0.823(3) 0.3368(11) 0.6988(19) 0.085 Uiso 1 d . . . H20B H 0.829(3) 0.2786(12) 0.7598(18) 0.085 Uiso 1 d . . . H20C H 0.920(3) 0.3355(10) 0.8199(18) 0.085 Uiso 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 Si1 0.03097(17) 0.03028(16) 0.03307(17) -0.00145(12) 0.00715(12) -0.00095(12) Si2 0.02995(16) 0.04138(19) 0.02774(16) -0.00358(13) 0.00772(12) -0.00226(13) Si6 0.0464(2) 0.0443(2) 0.0389(2) -0.01137(16) 0.00238(16) -0.00185(16) Si9 0.03604(19) 0.03186(18) 0.0455(2) 0.00327(15) 0.00254(15) -0.00140(14) C3 0.0331(6) 0.0460(7) 0.0352(6) -0.0037(5) 0.0041(5) -0.0013(5) C4 0.0347(6) 0.0458(7) 0.0298(6) -0.0013(5) 0.0029(5) -0.0074(5) C5 0.0417(7) 0.0469(7) 0.0357(6) -0.0040(6) 0.0060(5) -0.0055(6) C7 0.0428(7) 0.0452(8) 0.0436(7) -0.0066(6) 0.0075(6) 0.0003(6) C8 0.0398(7) 0.0341(7) 0.0487(8) 0.0005(6) 0.0038(6) -0.0030(5) C10 0.0377(7) 0.0392(7) 0.0507(8) 0.0010(6) 0.0022(6) -0.0009(5) C11 0.0308(6) 0.0388(7) 0.0474(7) -0.0014(6) -0.0005(5) -0.0019(5) C12 0.0373(7) 0.0337(6) 0.0543(9) -0.0058(6) -0.0025(6) -0.0015(5) C13 0.0593(10) 0.0350(7) 0.0654(10) 0.0058(7) 0.0115(8) 0.0047(7) C14 0.0569(9) 0.0565(9) 0.0429(8) -0.0079(7) 0.0223(7) -0.0121(8) C15 0.0476(8) 0.0671(11) 0.0502(9) -0.0169(8) 0.0194(7) 0.0022(8) C16 0.0488(8) 0.0585(9) 0.0357(7) 0.0081(6) 0.0070(6) -0.0051(7) C17 0.0704(12) 0.1041(16) 0.0415(9) -0.0180(10) 0.0080(8) 0.0144(12) C18 0.0789(14) 0.0500(10) 0.0955(16) -0.0105(11) -0.0059(12) -0.0193(10) C19 0.0684(11) 0.0547(9) 0.0502(9) 0.0084(8) 0.0009(8) -0.0071(9) C20 0.0423(8) 0.0411(8) 0.0880(13) 0.0025(8) 0.0168(8) -0.0011(6) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag Si1 C14 1.8561(15) . ? Si1 C13 1.8711(16) . ? Si1 C12 1.9001(15) . ? Si1 Si2 2.3466(5) . ? Si2 C16 1.8611(16) . ? Si2 C15 1.8657(16) . ? Si2 C3 1.9011(14) . ? Si6 C5 1.8293(15) . ? Si6 C18 1.857(2) . ? Si6 C17 1.859(2) . ? Si6 C7 1.8662(15) . ? Si9 C10 1.8340(15) . ? Si9 C20 1.8540(18) . ? Si9 C19 1.8563(18) . ? Si9 C8 1.8667(15) . ? C3 C4 1.4539(19) . ? C3 H3A 0.963(17) . ? C3 H3B 0.922(16) . ? C4 C5 1.197(2) . ? C7 C8 1.537(2) . ? C7 H7A 0.95(2) . ? C7 H7B 0.964(19) . ? C8 H8A 0.943(18) . ? C8 H8B 0.929(18) . ? C10 C11 1.197(2) . ? C11 C12 1.4574(19) . ? C12 H12A 0.953(19) . ? C12 H12B 0.955(19) . ? C13 H13A 0.94(2) . ? C13 H13B 0.94(2) . ? C13 H13C 0.95(2) . ? C14 H14A 0.93(2) . ? C14 H14B 0.93(2) . ? C14 H14C 0.93(2) . ? C15 H15A 0.91(2) . ? C15 H15B 0.94(2) . ? C15 H15C 0.96(2) . ? C16 H16A 0.88(2) . ? C16 H16B 0.92(2) . ? C16 H16C 0.97(2) . ? C17 H17A 0.94(3) . ? C17 H17B 0.91(3) . ? C17 H17C 0.97(3) . ? C18 H18A 0.91(3) . ? C18 H18B 0.93(3) . ? C18 H18C 0.91(3) . ? C19 H19A 0.98(2) . ? C19 H19B 0.94(2) . ? C19 H19C 0.93(2) . ? C20 H20A 0.96(2) . ? C20 H20B 0.92(2) . ? C20 H20C 0.98(2) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C14 Si1 C13 108.11(9) . . ? C14 Si1 C12 108.27(8) . . ? C13 Si1 C12 107.63(8) . . ? C14 Si1 Si2 114.13(6) . . ? C13 Si1 Si2 109.79(6) . . ? C12 Si1 Si2 108.71(5) . . ? C16 Si2 C15 107.55(9) . . ? C16 Si2 C3 108.47(7) . . ? C15 Si2 C3 108.81(7) . . ? C16 Si2 Si1 112.90(6) . . ? C15 Si2 Si1 109.76(6) . . ? C3 Si2 Si1 109.26(5) . . ? C5 Si6 C18 109.51(10) . . ? C5 Si6 C17 109.13(9) . . ? C18 Si6 C17 110.20(12) . . ? C5 Si6 C7 106.65(7) . . ? C18 Si6 C7 110.89(9) . . ? C17 Si6 C7 110.39(9) . . ? C10 Si9 C20 110.68(7) . . ? C10 Si9 C19 108.12(8) . . ? C20 Si9 C19 110.57(10) . . ? C10 Si9 C8 107.12(6) . . ? C20 Si9 C8 110.60(8) . . ? C19 Si9 C8 109.66(8) . . ? C4 C3 Si2 110.70(9) . . ? C4 C3 H3A 111.3(10) . . ? Si2 C3 H3A 107.2(10) . . ? C4 C3 H3B 113.0(10) . . ? Si2 C3 H3B 106.5(10) . . ? H3A C3 H3B 107.9(14) . . ? C5 C4 C3 175.26(13) . . ? C4 C5 Si6 173.08(12) . . ? C8 C7 Si6 114.04(10) . . ? C8 C7 H7A 109.3(12) . . ? Si6 C7 H7A 110.5(12) . . ? C8 C7 H7B 110.8(10) . . ? Si6 C7 H7B 106.4(11) . . ? H7A C7 H7B 105.5(16) . . ? C7 C8 Si9 115.34(10) . . ? C7 C8 H8A 108.2(10) . . ? Si9 C8 H8A 107.0(11) . . ? C7 C8 H8B 107.3(11) . . ? Si9 C8 H8B 109.0(11) . . ? H8A C8 H8B 110.0(15) . . ? C11 C10 Si9 171.93(13) . . ? C10 C11 C12 175.34(14) . . ? C11 C12 Si1 110.68(9) . . ? C11 C12 H12A 111.5(11) . . ? Si1 C12 H12A 108.9(11) . . ? C11 C12 H12B 108.9(11) . . ? Si1 C12 H12B 110.0(11) . . ? H12A C12 H12B 106.7(15) . . ? Si1 C13 H13A 108.6(13) . . ? Si1 C13 H13B 113.1(13) . . ? H13A C13 H13B 106.0(18) . . ? Si1 C13 H13C 109.6(13) . . ? H13A C13 H13C 107.5(18) . . ? H13B C13 H13C 111.7(19) . . ? Si1 C14 H14A 110.5(13) . . ? Si1 C14 H14B 113.6(13) . . ? H14A C14 H14B 108.1(18) . . ? Si1 C14 H14C 110.7(13) . . ? H14A C14 H14C 105.3(17) . . ? H14B C14 H14C 108.3(18) . . ? Si2 C15 H15A 109.0(14) . . ? Si2 C15 H15B 111.6(13) . . ? H15A C15 H15B 109.8(19) . . ? Si2 C15 H15C 106.7(13) . . ? H15A C15 H15C 109.5(18) . . ? H15B C15 H15C 110.1(18) . . ? Si2 C16 H16A 109.2(14) . . ? Si2 C16 H16B 113.2(13) . . ? H16A C16 H16B 108.2(18) . . ? Si2 C16 H16C 109.0(11) . . ? H16A C16 H16C 104.9(17) . . ? H16B C16 H16C 112.0(17) . . ? Si6 C17 H17A 111.5(16) . . ? Si6 C17 H17B 108.1(17) . . ? H17A C17 H17B 111(2) . . ? Si6 C17 H17C 110.6(15) . . ? H17A C17 H17C 107(2) . . ? H17B C17 H17C 108(2) . . ? Si6 C18 H18A 112.5(18) . . ? Si6 C18 H18B 110.2(18) . . ? H18A C18 H18B 108(2) . . ? Si6 C18 H18C 109.7(17) . . ? H18A C18 H18C 108(2) . . ? H18B C18 H18C 109(2) . . ? Si9 C19 H19A 111.6(14) . . ? Si9 C19 H19B 108.3(14) . . ? H19A C19 H19B 108.6(19) . . ? Si9 C19 H19C 107.1(14) . . ? H19A C19 H19C 110(2) . . ? H19B C19 H19C 111(2) . . ? Si9 C20 H20A 113.6(14) . . ? Si9 C20 H20B 111.7(14) . . ? H20A C20 H20B 102.0(19) . . ? Si9 C20 H20C 110.4(13) . . ? H20A C20 H20C 109.2(18) . . ? H20B C20 H20C 109.6(18) . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C14 Si1 Si2 C16 93.16(9) . . . . ? C13 Si1 Si2 C16 -145.30(9) . . . . ? C12 Si1 Si2 C16 -27.80(8) . . . . ? C14 Si1 Si2 C15 -146.87(10) . . . . ? C13 Si1 Si2 C15 -25.33(9) . . . . ? C12 Si1 Si2 C15 92.18(8) . . . . ? C14 Si1 Si2 C3 -27.63(9) . . . . ? C13 Si1 Si2 C3 93.91(8) . . . . ? C12 Si1 Si2 C3 -148.59(7) . . . . ? C16 Si2 C3 C4 -53.19(12) . . . . ? C15 Si2 C3 C4 -169.91(11) . . . . ? Si1 Si2 C3 C4 70.27(10) . . . . ? Si2 C3 C4 C5 7.1(18) . . . . ? C3 C4 C5 Si6 -16(3) . . . . ? C18 Si6 C5 C4 118.6(11) . . . . ? C17 Si6 C5 C4 -120.7(11) . . . . ? C7 Si6 C5 C4 -1.5(11) . . . . ? C5 Si6 C7 C8 71.93(12) . . . . ? C18 Si6 C7 C8 -47.23(15) . . . . ? C17 Si6 C7 C8 -169.65(12) . . . . ? Si6 C7 C8 Si9 -162.22(8) . . . . ? C10 Si9 C8 C7 68.12(13) . . . . ? C20 Si9 C8 C7 -52.58(13) . . . . ? C19 Si9 C8 C7 -174.78(12) . . . . ? C20 Si9 C10 C11 154.3(10) . . . . ? C19 Si9 C10 C11 -84.5(10) . . . . ? C8 Si9 C10 C11 33.6(10) . . . . ? Si9 C10 C11 C12 -36(3) . . . . ? C10 C11 C12 Si1 -6(2) . . . . ? C14 Si1 C12 C11 -54.33(13) . . . . ? C13 Si1 C12 C11 -170.97(12) . . . . ? Si2 Si1 C12 C11 70.16(12) . . . . ? _diffrn_measured_fraction_theta_max 0.973 _diffrn_reflns_theta_full 27.98 _diffrn_measured_fraction_theta_full 0.973 _refine_diff_density_max 0.27 _refine_diff_density_min -0.22 _refine_diff_density_rms 0.045 #===END