# Supplementary Material (ESI) for Perkin Transactions # This journal is © The Royal Society of Chemistry 2001 # CCDC Number: 156257 data_CEFRQ8 _database_code_CSD 156257 _journal_coden_Cambridge 188 # 1. SUBMISSION DETAILS _publ_contact_autor ; Prof Binne Zwanenburg Department of Organic Chemistry University of Nijmegen 6525 ED Nijmegen 6525 ED NETHERLANDS ; _publ_requested_journal 'Perkin Transactions 2' _publ_requested_coeditor_name ? _publ_contact_letter ; ; #============================================================================== # 3. AUTHOR LIST loop_ _publ_author_name _publ_author_address 'G.J. Kemperman' ; Department of Organic Chemistry Nijmegen SON Research Center University of Nijmegen Toernooiveld 1 6525 ED Nijmegen The Netherlands ; 'R. de Gelder' ; Department of Inorganic Chemistry Nijmegen SON Research Center University of Nijmegen Toernooiveld 1 6525 ED Nijmegen The Netherlands ; 'F.J. Dommerholt' ; Department of Organic Chemistry Nijmegen SON Research Center University of Nijmegen Toernooiveld 1 6525 ED Nijmegen The Netherlands ; 'P.C. Raemakers-Franken' ; DSM Research Department of Organic Chemistry and Biotechnology P.O. Box 18 6160 MD Geleen The Netherlands ; 'A.J.H. Klunder' ; Department of Organic Chemistry Nijmegen SON Research Center University of Nijmegen Toernooiveld 1 6525 ED Nijmegen The Netherlands ; 'B. Zwanenburg' ; Department of Organic Chemistry Nijmegen SON Research Center University of Nijmegen Toernooiveld 1 6525 ED Nijmegen The Netherlands ; #============================================================================== # 4. TEXT _publ_section_title ; Efficiency of Cephalosporin Complexation with Aromatic Compounds. ; _publ_section_abstract ; ; _publ_section_references ; Beurskens, P. T., Beurskens, G., Bosman, W. P., Gelder, R. de, Garc\'ia-Granda, S., Gould, R. O., Isra\"el, R. & Smits, J. M. M. (1996). DIRDIF-96, A computer program system for crystal structure determination by Patterson methods and direct methods applied to difference structure factors. Crystallography Laboratory, University of Nijmegen, The Netherlands. CAD4 EXPRESS Enraf-Nonius diffractometer control software (1994). Release 5.1, Enraf-Nonius Delft, The Netherlands. Grant, D. F. & Gabe, E. J. (1978). J. Appl. Cryst. 11, 114--120. International Tables for X-ray Crystallography (1974). Vol. IV, Birmingham, England: Kynoch Press. Lehman, M. S. & Larsen, F. K. (1974). Acta Cryst. A30, 580--584. North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351--359. Sheldrick, G. M. (1997). SHELXL-97, Program for the refinement of crystal structures. University of G\"ottingen, Germany. Smits, J. M. M., Behm, H., Bosman, W. P. & Beurskens, P. T. (1988). J. Crystallogr. Spectrosc. Res. 18, 447--450. Spek, A. L. (1990). Acta Cryst. A46, C-34. Spek, A. L. (1993). PLUTON, A program for plotting molecular and crystal structures. University of Utrecht, The Netherlands. Spek, A. L. (1995). PLATON-93, Program for display and analysis of crystal and molecular structures. University of Utrecht, The Netherlands. ; _publ_section_figure_captions ; ; _publ_section_acknowledgements ; ; #============================================================================== _audit_creation_method 'SHELXL, adapted and expanded' _audit_creation_date 2000-03-16 _chemical_name_systematic ; Cephradine/8-hydroxy quinoline complex ; _chemical_name_common ? _chemical_formula_moiety ? _chemical_formula_sum 'C41 H58 N7 O15.50 S2' _chemical_formula_weight 961.06 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' 'N' 'N' 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'O' 'O' 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 'S' 'S' 0.1246 0.1234 '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' loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y, -z' 'x+1/2, y+1/2, z' '-x+1/2, y+1/2, -z' _cell_length_a 23.443(4) _cell_length_b 7.0872(12) _cell_length_c 14.896(6) _cell_angle_alpha 90.00 _cell_angle_beta 108.61(2) _cell_angle_gamma 90.00 _cell_volume 2345.5(12) _cell_formula_units_Z 2 _cell_measurement_temperature 293(2) _cell_measurement_reflns_used 16 _cell_measurement_theta_min 8.756 _cell_measurement_theta_max 19.803 _exptl_crystal_description 'rather regular rod' _exptl_crystal_colour 'transparent colourless' _exptl_crystal_size_max 0.50 _exptl_crystal_size_mid 0.23 _exptl_crystal_size_min 0.17 #_exptl_crystal_density_meas 'not measured' _exptl_crystal_density_diffrn 1.361 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 1018 _exptl_absorpt_coefficient_mu 0.189 _exptl_absorpt_correction_type experimental #_exptl_absorpt_process_details '(North, Phillips & Mathews, 1968)' _exptl_absorpt_correction_T_min 0.970 _exptl_absorpt_correction_T_max 1.046 _exptl_special_details ; ? ; _diffrn_ambient_temperature 293(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 'Nonius CAD4' _diffrn_measurement_method \w/2\q-scan _diffrn_special_details ; \w/2\q-scan with variable scan width, variable scan speed and variable aperture. Scan width (0.50 + 0.52tan\q)\%, range: 0.78\%-1.15\%, aperture (1.40 + 0.53tan\q)mm., range: 1.42-1.67mm. Maximum scan time: 30 sec/reflection. ; _diffrn_detector_area_resol_mean ? _diffrn_standards_number 3 _diffrn_standards_interval_time 6947 _diffrn_standards_decay_% 7.813 _diffrn_reflns_number 2983 _diffrn_reflns_av_R_equivalents 0.0212 _diffrn_reflns_av_sigmaI/netI 0.0351 _diffrn_reflns_limit_h_min -30 _diffrn_reflns_limit_h_max 0 _diffrn_reflns_limit_k_min -9 _diffrn_reflns_limit_k_max 0 _diffrn_reflns_limit_l_min -18 _diffrn_reflns_limit_l_max 19 _diffrn_reflns_theta_min 2.67 _diffrn_reflns_theta_max 27.46 _reflns_number_total 2911 _reflns_number_gt 2238 _reflns_number_observed 2238 _reflns_threshold_expression >2sigma(I) _reflns_observed_criterion >2sigma(I) _computing_data_collection ; CAD4 EXPRESS (Enraf-Nonius, 1994) ; #_computing_cell_refinement #; #CAD4 EXPRESS (Enraf-Nonius, 1994) #; _computing_data_reduction ; local programs (Smits et al., 1988), profile analysis (Lehman & Larsen, 1974, Grant & Gabe, 1978), EMPABS (North et al., 1968) ; _computing_structure_solution ; DIRDIF (Beurskens et al., 1996), ; _computing_structure_refinement 'SHELXL-97 (Sheldrick, 1997)' _computing_molecular_graphics ; PLUTON (Spek, 1993), PLATON (Spek, 1990, 1995) ; _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 ; w=1/[\s^2^(Fo^2^)+(0.0802P)^2^+1.5624P] 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_abs_structure_Flack 0.00(16) _refine_ls_number_reflns 2911 _refine_ls_number_parameters 306 _refine_ls_number_restraints 1 _refine_ls_R_factor_all 0.0768 _refine_ls_R_factor_gt 0.0542 _refine_ls_R_factor_obs 0.0542 _refine_ls_wR_factor_ref 0.1511 _refine_ls_wR_factor_all 0.1511 _refine_ls_wR_factor_gt 0.1373 _refine_ls_wR_factor_obs 0.1373 _refine_ls_goodness_of_fit_ref 1.077 _refine_ls_goodness_of_fit_all 1.077 _refine_ls_restrained_S_all 1.077 _refine_ls_shift/su_max 0.005 _refine_ls_shift/esd_max 0.005 _refine_ls_shift/su_mean 0.001 _refine_ls_shift/esd_mean 0.001 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 S1 S -0.16950(5) 0.07211(19) 0.32356(8) 0.0483(3) Uani 1 d . . . C2 C -0.0909(2) 0.1380(7) 0.3723(3) 0.0450(11) Uani 1 d . . . H2A H -0.0889 0.2584 0.4041 0.054 Uiso 1 calc R . . H2B H -0.0712 0.0458 0.4203 0.054 Uiso 1 calc R . . C3 C -0.05464(18) 0.1548(7) 0.3051(3) 0.0378(9) Uani 1 d . . . C4 C -0.07902(17) 0.1794(6) 0.2121(3) 0.0349(9) Uani 1 d . . . N5 N -0.14230(13) 0.1965(5) 0.1726(2) 0.0332(8) Uani 1 d . . . C6 C -0.18470(17) 0.2296(6) 0.2245(3) 0.0352(9) Uani 1 d . . . H6 H -0.1875 0.3622 0.2412 0.042 Uiso 1 calc R . . C7 C -0.23565(17) 0.1667(7) 0.1336(3) 0.0369(9) Uani 1 d . . . H7 H -0.2606 0.2732 0.1017 0.044 Uiso 1 calc R . . C8 C -0.18364(16) 0.1278(6) 0.0940(3) 0.0342(9) Uani 1 d . . . C9 C -0.04445(17) 0.2101(7) 0.1439(3) 0.0393(10) Uani 1 d . . . C10 C 0.0122(2) 0.1555(10) 0.3558(3) 0.0562(13) Uani 1 d . . . H10A H 0.0331 0.1870 0.3118 0.084 Uiso 1 calc R . . H10B H 0.0247 0.0327 0.3820 0.084 Uiso 1 calc R . . H10C H 0.0216 0.2471 0.4058 0.084 Uiso 1 calc R . . O11 O 0.00143(14) 0.1152(6) 0.1525(3) 0.0600(11) Uani 1 d . . . O12 O -0.06438(14) 0.3379(6) 0.0832(2) 0.0491(8) Uani 1 d . . . O13 O -0.18010(12) 0.0566(6) 0.02184(19) 0.0454(8) Uani 1 d . . . N14 N -0.27108(14) 0.0050(5) 0.1381(3) 0.0382(8) Uani 1 d . . . H14 H -0.2548 -0.1051 0.1450 0.046 Uiso 1 calc R . . C15 C -0.32877(17) 0.0218(6) 0.1316(3) 0.0354(9) Uani 1 d . . . O16 O -0.35568(15) 0.1714(6) 0.1203(3) 0.0644(11) Uani 1 d . . . C17 C -0.36031(17) -0.1637(7) 0.1387(3) 0.0349(9) Uani 1 d . . . H17 H -0.3514 -0.2550 0.0956 0.042 Uiso 1 calc R . . N18 N -0.42660(14) -0.1244(7) 0.1045(2) 0.0442(10) Uani 1 d . . . H18A H -0.4460 -0.2174 0.1226 0.066 Uiso 1 calc R . . H18B H -0.4394 -0.1165 0.0416 0.066 Uiso 1 calc R . . H18C H -0.4338 -0.0159 0.1290 0.066 Uiso 1 calc R . . C19 C -0.34042(18) -0.2465(7) 0.2368(3) 0.0371(10) Uani 1 d . . . C20 C -0.3391(3) -0.1230(8) 0.3172(3) 0.0537(13) Uani 1 d . . . H20A H -0.3787 -0.0678 0.3056 0.064 Uiso 1 calc R . . H20B H -0.3109 -0.0209 0.3208 0.064 Uiso 1 calc R . . C21 C -0.3215(3) -0.2245(11) 0.4100(4) 0.0661(17) Uani 1 d . . . H21 H -0.3208 -0.1567 0.4637 0.079 Uiso 1 calc R . . C22 C -0.3067(3) -0.4040(12) 0.4199(4) 0.077(2) Uani 1 d . . . H22 H -0.2964 -0.4564 0.4802 0.093 Uiso 1 calc R . . C23 C -0.3058(4) -0.5235(11) 0.3426(5) 0.085(2) Uani 1 d . . . H23A H -0.3317 -0.6312 0.3403 0.102 Uiso 1 calc R . . H23B H -0.2652 -0.5706 0.3545 0.102 Uiso 1 calc R . . C24 C -0.3257(3) -0.4269(9) 0.2481(4) 0.0577(12) Uani 1 d . . . H24 H -0.3279 -0.4978 0.1946 0.069 Uiso 1 calc R . . O30 O -0.4132(7) 0.164(3) 0.4046(12) 0.145(5) Uani 0.50 d P A 1 H30B H -0.3763 0.1649 0.4208 0.218 Uiso 0.50 calc PR A 1 C30 C -0.6115(4) 0.1518(12) 0.4365(8) 0.104(3) Uani 1 d . . . H30A H -0.6526 0.1530 0.4273 0.125 Uiso 1 calc R . . C31 C -0.5902(5) 0.1504(11) 0.3602(7) 0.102(3) Uani 1 d . . . H31 H -0.6179 0.1494 0.2995 0.122 Uiso 1 calc R B 1 N32 N -0.5335(4) 0.1505(10) 0.3694(5) 0.0902(19) Uani 0.50 d P C 1 C32 C -0.5335(4) 0.1505(10) 0.3694(5) 0.0902(19) Uani 0.50 d P C 2 H32 H -0.5209 0.1499 0.3162 0.108 Uiso 0.50 calc PR C 2 C33 C -0.4911(3) 0.1516(9) 0.4604(4) 0.0695(16) Uani 1 d . . . C34 C -0.4291(4) 0.1513(11) 0.4742(6) 0.086(2) Uani 1 d . . . H34 H -0.4155 0.1507 0.4221 0.103 Uiso 0.50 calc PR D 2 O40 O 0.28272(16) 0.1507(6) 0.1356(3) 0.0582(9) Uani 1 d . . . O50 O 0.3915(2) 0.1837(9) 0.1061(3) 0.0832(13) Uani 1 d . . . O60 O -0.4691(3) 0.2151(12) 0.1950(5) 0.131(2) Uani 1 d . . . O70 O 0.0000 -0.207(8) 0.0000 0.43(4) Uani 0.50 d SP . . 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 S1 0.0525(6) 0.0578(7) 0.0393(5) 0.0097(6) 0.0214(5) -0.0076(6) C2 0.061(3) 0.041(3) 0.0286(19) 0.0012(19) 0.0082(18) -0.008(2) C3 0.039(2) 0.035(2) 0.0333(19) 0.0043(18) 0.0027(15) -0.010(2) C4 0.0311(18) 0.034(2) 0.0377(19) 0.0016(18) 0.0090(15) -0.0081(18) N5 0.0273(15) 0.043(2) 0.0307(15) 0.0042(15) 0.0116(12) -0.0073(15) C6 0.0370(19) 0.034(2) 0.0389(19) 0.0020(18) 0.0181(16) -0.0041(18) C7 0.0298(18) 0.036(2) 0.045(2) 0.004(2) 0.0123(16) -0.0049(18) C8 0.0278(17) 0.037(2) 0.036(2) 0.0102(17) 0.0081(15) -0.0039(16) C9 0.0252(18) 0.051(3) 0.039(2) -0.001(2) 0.0070(15) -0.0120(19) C10 0.046(2) 0.062(3) 0.046(2) 0.006(3) -0.005(2) -0.007(3) O11 0.0364(16) 0.070(3) 0.079(2) 0.019(2) 0.0267(16) 0.0050(17) O12 0.0434(16) 0.064(2) 0.0418(15) 0.0135(17) 0.0168(13) -0.0019(17) O13 0.0374(14) 0.065(2) 0.0344(14) -0.0068(17) 0.0122(11) -0.0068(17) N14 0.0263(16) 0.0344(19) 0.055(2) 0.0046(17) 0.0145(15) -0.0001(15) C15 0.0298(19) 0.040(2) 0.0387(19) -0.0054(18) 0.0143(16) -0.0033(18) O16 0.0414(18) 0.047(2) 0.112(3) 0.001(2) 0.0346(19) 0.0038(17) C17 0.0279(18) 0.042(2) 0.0387(19) -0.0112(19) 0.0162(16) -0.0071(18) N18 0.0289(17) 0.067(3) 0.0366(17) -0.0003(19) 0.0105(14) -0.0133(18) C19 0.032(2) 0.042(3) 0.041(2) -0.0065(19) 0.0179(17) -0.0099(18) C20 0.064(3) 0.055(3) 0.041(2) -0.010(2) 0.017(2) -0.001(3) C21 0.069(3) 0.090(5) 0.037(2) -0.005(3) 0.014(2) 0.002(4) C22 0.083(4) 0.099(6) 0.050(3) 0.024(4) 0.022(3) 0.024(4) C23 0.113(5) 0.063(4) 0.083(4) 0.023(4) 0.038(4) 0.019(4) C24 0.075(3) 0.046(3) 0.057(3) 0.000(3) 0.029(2) 0.001(3) O30 0.158(12) 0.113(11) 0.177(14) -0.031(11) 0.070(11) 0.030(12) C30 0.104(6) 0.051(4) 0.153(8) 0.010(6) 0.035(6) -0.005(4) C31 0.129(7) 0.044(3) 0.101(6) -0.001(4) -0.007(6) -0.009(5) N32 0.127(6) 0.050(3) 0.084(4) -0.003(3) 0.020(4) 0.000(4) C32 0.127(6) 0.050(3) 0.084(4) -0.003(3) 0.020(4) 0.000(4) C33 0.112(5) 0.038(3) 0.058(3) 0.000(3) 0.026(3) -0.004(3) C34 0.132(7) 0.050(3) 0.092(5) -0.016(4) 0.059(5) -0.002(4) O40 0.061(2) 0.051(2) 0.059(2) 0.0020(18) 0.0134(16) 0.0086(19) O50 0.076(3) 0.095(4) 0.082(3) 0.005(3) 0.029(2) 0.014(3) O60 0.129(5) 0.115(6) 0.148(5) 0.000(5) 0.044(4) 0.014(5) O70 0.67(10) 0.19(5) 0.23(4) 0.000 -0.12(5) 0.000 _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 S1 C6 1.793(4) . Y S1 C2 1.813(5) . Y C2 C3 1.510(6) . Y C3 C4 1.331(5) . Y C3 C10 1.508(6) . Y C4 N5 1.416(5) . Y C4 C9 1.503(6) . Y N5 C8 1.351(5) . Y N5 C6 1.459(5) . Y C6 C7 1.557(6) . Y C7 N14 1.429(6) . Y C7 C8 1.540(6) . Y C8 O13 1.214(5) . Y C9 O11 1.240(5) . Y C9 O12 1.260(6) . Y N14 C15 1.330(5) . Y C15 O16 1.218(6) . Y C15 C17 1.528(6) . Y C17 N18 1.499(5) . Y C17 C19 1.505(6) . Y C19 C24 1.320(8) . Y C19 C20 1.475(6) . Y C20 C21 1.495(8) . Y C21 C22 1.314(11) . Y C22 C23 1.435(10) . Y C23 C24 1.500(9) . Y O30 C34 1.213(16) . Y C30 C34 1.367(12) 2_456 Y C30 C31 1.379(13) . Y C31 N32 1.292(12) . Y N32 C33 1.402(9) . Y C33 C33 1.371(12) 2_456 Y C33 C34 1.400(10) . Y C34 C30 1.367(12) 2_456 Y 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 C6 S1 C2 94.5(2) . . Y C3 C2 S1 118.0(3) . . Y C4 C3 C10 123.6(4) . . Y C4 C3 C2 123.7(4) . . Y C10 C3 C2 112.6(4) . . Y C3 C4 N5 119.2(3) . . Y C3 C4 C9 125.3(4) . . Y N5 C4 C9 115.2(3) . . Y C8 N5 C4 134.1(4) . . Y C8 N5 C6 95.5(3) . . Y C4 N5 C6 126.5(3) . . Y N5 C6 C7 87.5(3) . . Y N5 C6 S1 110.2(3) . . Y C7 C6 S1 115.7(3) . . Y N14 C7 C8 114.6(4) . . Y N14 C7 C6 119.0(4) . . Y C8 C7 C6 84.4(3) . . Y O13 C8 N5 133.3(4) . . Y O13 C8 C7 134.4(4) . . Y N5 C8 C7 92.3(3) . . Y O11 C9 O12 125.0(4) . . Y O11 C9 C4 119.3(4) . . Y O12 C9 C4 115.6(4) . . Y C15 N14 C7 121.1(4) . . Y O16 C15 N14 123.9(4) . . Y O16 C15 C17 121.2(3) . . Y N14 C15 C17 114.9(4) . . Y N18 C17 C19 111.7(3) . . Y N18 C17 C15 106.8(4) . . Y C19 C17 C15 113.3(3) . . Y C24 C19 C20 122.3(5) . . Y C24 C19 C17 119.3(4) . . Y C20 C19 C17 118.4(4) . . Y C19 C20 C21 113.1(5) . . Y C22 C21 C20 123.7(6) . . Y C21 C22 C23 123.5(6) . . Y C22 C23 C24 113.8(6) . . Y C19 C24 C23 123.5(6) . . Y C34 C30 C31 118.6(9) 2_456 . Y N32 C31 C30 122.9(8) . . Y C31 N32 C33 119.4(8) . . Y C33 C33 C34 117.4(8) 2_456 . Y C33 C33 N32 120.9(9) 2_456 . Y C34 C33 N32 121.6(6) . . Y O30 C34 C30 121.6(12) . 2_456 Y O30 C34 C33 117.6(11) . . Y C30 C34 C33 120.7(7) 2_456 . Y _diffrn_reflns_theta_full 27.46 _refine_diff_density_max 0.393 _refine_diff_density_min -0.226 _refine_diff_density_rms 0.057 _publ_section_experimental ; Crystal colour: transparent colourless, crystal shape: rather regular rod. Profile analysis combining the methods of Lehman & Larsen (1974) and Grant & Gabe (1978). Empirical absorption correction using EMPABS (North, Phillips & Mathews, 1968). Data collection parameters: \w/2\q-scan with variable scan width, variable scan speed and variable aperture. Scan width (0.50 + 0.52tan\q)\%, range: 0.78\%-1.15\%, aperture (1.40 + 0.53tan\q)mm., range: 1.42-1.67mm. Maximum scan time: 30 sec/reflection. Least-squares refinement using calculated weights: w=1/[\s^2^(Fo^2^)+(0.0802P)^2^+1.5624P] where P=(Fo^2^+2Fc^2^)/3 ;