# Electronic Supplementary Material (ESI) for Chemical Science.
# This journal is © The Royal Society of Chemistry 2016

####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
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data_3756
_database_code_depnum_ccdc_archive 'CCDC 1471165'
_audit_update_record             
;
2016-03-29 deposited with the CCDC.
2016-05-09 downloaded from the CCDC.
;

_audit_creation_method           SHELXL-2014/7
_shelx_SHELXL_version_number     2014/7
_chemical_name_systematic        ?
_chemical_name_common            ?
_chemical_melting_point          ?
_chemical_formula_moiety         'C54 H73 N4 Si2'
_chemical_formula_sum            'C54 H73 N4 Si2'
_chemical_formula_weight         834.34

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'
Si Si 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_H-M_alt        'P 21/c'
_space_group_name_Hall           '-P 2ybc'

_shelx_space_group_comment       
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;

loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x, y+1/2, -z+1/2'
'-x, -y, -z'
'x, -y-1/2, z-1/2'

_cell_length_a                   12.9588(11)
_cell_length_b                   13.5352(9)
_cell_length_c                   18.2226(15)
_cell_angle_alpha                90
_cell_angle_beta                 126.432(5)
_cell_angle_gamma                90
_cell_volume                     2571.6(4)
_cell_formula_units_Z            2
_cell_measurement_temperature    123(2)
_cell_measurement_reflns_used    3919
_cell_measurement_theta_min      2.71
_cell_measurement_theta_max      26.97
_exptl_crystal_density_diffrn    1.078
_exptl_crystal_F_000             906
_exptl_transmission_factor_min   ?
_exptl_transmission_factor_max   ?
_exptl_crystal_size_max          0.24
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.12
_exptl_absorpt_coefficient_mu    0.106
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_correction_T_min  0.6417
_exptl_absorpt_correction_T_max  0.9185
_exptl_absorpt_process_details   'XRed, STOE & CIE, 2011'
_exptl_special_details           
; 
 ? 
;


_exptl_crystal_colour            'clear dark blue'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   dark
_exptl_crystal_colour_primary    blue
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block


_diffrn_measurement_device       '2-circle goniometer'
_diffrn_measurement_device_type  'STOE IPDS 2T'
_diffrn_detector                 'image plate (34 cm diameter)'
_diffrn_detector_type            STOE
_diffrn_detector_area_resol_mean 6.67
_diffrn_source                   
'sealed X-ray tube, 12 x 0.4 mm long-fine focus'
_diffrn_source_voltage           50
_diffrn_source_current           40
_diffrn_source_power             2.00
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_monochromator  'plane graphite'
_diffrn_radiation_polarisn_norm  0
_diffrn_radiation_collimation    '0.5 mm diameter, monocapillary'
_diffrn_measurement_method       'rotation method'
_diffrn_measurement_details      
; 171 frames, detector distance = 100 mm, exposure time = 4min
;

_diffrn_ambient_temperature      123(2)
_diffrn_reflns_number            20621
_diffrn_reflns_av_unetI/netI     0.2106
_diffrn_reflns_av_R_equivalents  0.1649
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_theta_min         2.712
_diffrn_reflns_theta_max         27.997
_diffrn_reflns_theta_full        25.242
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measured_fraction_theta_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_point_group_measured_fraction_full 0.999
_reflns_number_total             6197
_reflns_number_gt                2130
_reflns_threshold_expression     'I > 2σ(I)'
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_max     .
_reflns_Friedel_fraction_full    .

_reflns_special_details          
;
 Reflections were merged by SHELXL according to the crystal
 class for the calculation of statistics and refinement.
 
 _reflns_Friedel_fraction is defined as the number of unique
 Friedel pairs measured divided by the number that would be
 possible theoretically, ignoring centric projections and
 systematic absences.
;

_computing_data_collection       'STOE X-AREA, STOE&CIE, 2011'
_computing_cell_refinement       'STOE X-AREA, STOE&CIE, 2011'
_computing_data_reduction        'STOE X-RED, STOE&CIE, 2011'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_computing_molecular_graphics    'DIAMOND (Brandenburg, 1999)'
_computing_publication_material  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_refine_special_details          ?
_refine_ls_structure_factor_coef Fsqd
_refine_ls_matrix_type           full
_refine_ls_weighting_scheme      calc
_refine_ls_weighting_details     
'w=1/[σ²(Fo²)+(0.0929P)²] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_primary     ?
_atom_sites_solution_secondary   ?
_atom_sites_solution_hydrogens   mixed
_refine_ls_hydrogen_treatment    constr
_refine_ls_extinction_method     none
_refine_ls_extinction_coef       .
_refine_ls_number_reflns         6197
_refine_ls_number_parameters     279
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.1885
_refine_ls_R_factor_gt           0.0755
_refine_ls_wR_factor_ref         0.2042
_refine_ls_wR_factor_gt          0.1721
_refine_ls_goodness_of_fit_ref   0.754
_refine_ls_restrained_S_all      0.754
_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_site_symmetry_order
_atom_site_calc_flag
_atom_site_refinement_flags_posn
_atom_site_refinement_flags_adp
_atom_site_refinement_flags_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
Si Si 0.57085(13) -0.46010(9) -0.00743(9) 0.0580(4) Uani 1 1 d . . . . .
H H 0.5740 -0.4319 0.0411 0.070 Uiso 0.5 1 d R U P . .
N1 N 0.3545(3) -0.3664(2) -0.17949(19) 0.0341(7) Uani 1 1 d . . . . .
N2 N 0.5426(3) -0.32915(19) -0.14132(19) 0.0333(7) Uani 1 1 d . . . . .
C1 C 0.4826(3) -0.3835(2) -0.1109(2) 0.0308(8) Uani 1 1 d . . . . .
C2 C 0.3379(4) -0.3065(2) -0.2465(3) 0.0400(9) Uani 1 1 d . . . . .
H2 H 0.2581 -0.2854 -0.2999 0.048 Uiso 1 1 calc R U . . .
C3 C 0.4543(3) -0.2832(2) -0.2231(2) 0.0382(9) Uani 1 1 d . . . . .
H3 H 0.4725 -0.2426 -0.2566 0.046 Uiso 1 1 calc R U . . .
C4 C 0.2485(3) -0.3967(3) -0.1768(2) 0.0368(8) Uani 1 1 d . . . . .
C5 C 0.1809(3) -0.4807(3) -0.2268(2) 0.0434(9) Uani 1 1 d . . . . .
C6 C 0.0756(4) -0.5056(4) -0.2249(3) 0.0639(13) Uani 1 1 d . . . . .
H6 H 0.0240 -0.5612 -0.2584 0.077 Uiso 1 1 calc R U . . .
C7 C 0.0481(4) -0.4517(4) -0.1763(3) 0.0690(13) Uani 1 1 d . . . . .
H7 H -0.0216 -0.4711 -0.1755 0.083 Uiso 1 1 calc R U . . .
C8 C 0.1176(4) -0.3701(3) -0.1284(3) 0.0564(11) Uani 1 1 d . . . . .
H8 H 0.0943 -0.3326 -0.0962 0.068 Uiso 1 1 calc R U . . .
C9 C 0.2229(3) -0.3413(3) -0.1263(2) 0.0388(9) Uani 1 1 d . . . . .
C10 C 0.2081(4) -0.5393(3) -0.2831(3) 0.0471(9) Uani 1 1 d . . . . .
H10 H 0.2897 -0.5130 -0.2697 0.057 Uiso 1 1 calc R U . . .
C11 C 0.1047(4) -0.5241(4) -0.3842(3) 0.0645(12) Uani 1 1 d . . . . .
H11A H 0.0219 -0.5460 -0.3995 0.097 Uiso 1 1 calc R U . . .
H11B H 0.1256 -0.5627 -0.4192 0.097 Uiso 1 1 calc R U . . .
H11C H 0.0998 -0.4539 -0.3991 0.097 Uiso 1 1 calc R U . . .
C12 C 0.2291(6) -0.6484(3) -0.2594(4) 0.0774(15) Uani 1 1 d . . . . .
H12A H 0.2991 -0.6565 -0.1944 0.116 Uiso 1 1 calc R U . . .
H12B H 0.2515 -0.6820 -0.2958 0.116 Uiso 1 1 calc R U . . .
H12C H 0.1504 -0.6773 -0.2726 0.116 Uiso 1 1 calc R U . . .
C13 C 0.3007(4) -0.2503(3) -0.0724(3) 0.0481(10) Uani 1 1 d . . . . .
H13 H 0.3855 -0.2564 -0.0619 0.058 Uiso 1 1 calc R U . . .
C14 C 0.3280(5) -0.2423(3) 0.0199(3) 0.0640(12) Uani 1 1 d . . . . .
H14A H 0.2473 -0.2337 0.0126 0.096 Uiso 1 1 calc R U . . .
H14B H 0.3839 -0.1854 0.0525 0.096 Uiso 1 1 calc R U . . .
H14C H 0.3707 -0.3027 0.0548 0.096 Uiso 1 1 calc R U . . .
C15 C 0.2380(6) -0.1561(3) -0.1279(4) 0.0882(17) Uani 1 1 d . . . . .
H15A H 0.2203 -0.1634 -0.1879 0.132 Uiso 1 1 calc R U . . .
H15B H 0.2960 -0.1000 -0.0958 0.132 Uiso 1 1 calc R U . . .
H15C H 0.1575 -0.1443 -0.1355 0.132 Uiso 1 1 calc R U . . .
C16 C 0.6794(3) -0.3129(2) -0.0869(2) 0.0312(8) Uani 1 1 d . . . . .
C17 C 0.7534(3) -0.3795(2) -0.0958(2) 0.0364(8) Uani 1 1 d . . . . .
C18 C 0.8849(3) -0.3625(3) -0.0425(3) 0.0446(9) Uani 1 1 d . . . . .
H18 H 0.9388 -0.4062 -0.0464 0.053 Uiso 1 1 calc R U . . .
C19 C 0.9378(4) -0.2831(3) 0.0157(3) 0.0522(11) Uani 1 1 d . . . . .
H19 H 1.0277 -0.2726 0.0511 0.063 Uiso 1 1 calc R U . . .
C20 C 0.8630(4) -0.2183(3) 0.0240(3) 0.0474(10) Uani 1 1 d . . . . .
H20 H 0.9019 -0.1649 0.0659 0.057 Uiso 1 1 calc R U . . .
C21 C 0.7285(4) -0.2313(2) -0.0299(3) 0.0392(9) Uani 1 1 d . . . . .
C22 C 0.6940(3) -0.4646(3) -0.1618(2) 0.0388(8) Uani 1 1 d . . . . .
H22 H 0.6091 -0.4786 -0.1742 0.047 Uiso 1 1 calc R U . . .
C23 C 0.7746(4) -0.5598(3) -0.1227(3) 0.0519(11) Uani 1 1 d . . . . .
H23A H 0.8539 -0.5516 -0.1174 0.078 Uiso 1 1 calc R U . . .
H23B H 0.7255 -0.6153 -0.1636 0.078 Uiso 1 1 calc R U . . .
H23C H 0.7957 -0.5732 -0.0623 0.078 Uiso 1 1 calc R U . . .
C24 C 0.6690(4) -0.4380(3) -0.2512(3) 0.0575(11) Uani 1 1 d . . . . .
H24A H 0.6125 -0.3802 -0.2772 0.086 Uiso 1 1 calc R U . . .
H24B H 0.6277 -0.4938 -0.2935 0.086 Uiso 1 1 calc R U . . .
H24C H 0.7504 -0.4227 -0.2412 0.086 Uiso 1 1 calc R U . . .
C25 C 0.6476(4) -0.1577(3) -0.0224(3) 0.0473(10) Uani 1 1 d . . . . .
H25 H 0.5571 -0.1818 -0.0633 0.057 Uiso 1 1 calc R U . . .
C26 C 0.6805(6) -0.1497(4) 0.0710(4) 0.0809(16) Uani 1 1 d . . . . .
H26A H 0.6793 -0.2155 0.0928 0.121 Uiso 1 1 calc R U . . .
H26B H 0.6175 -0.1074 0.0690 0.121 Uiso 1 1 calc R U . . .
H26C H 0.7662 -0.1208 0.1124 0.121 Uiso 1 1 calc R U . . .
C27 C 0.6503(5) -0.0568(3) -0.0593(3) 0.0640(12) Uani 1 1 d . . . . .
H27A H 0.7373 -0.0295 -0.0202 0.096 Uiso 1 1 calc R U . . .
H27B H 0.5908 -0.0118 -0.0596 0.096 Uiso 1 1 calc R U . . .
H27C H 0.6246 -0.0644 -0.1215 0.096 Uiso 1 1 calc R U . . .


_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
Si C1 1.837(4) . ?
Si Si 2.281(3) 3_645 ?
Si H 0.9420 . ?
N1 C2 1.372(4) . ?
N1 C1 1.381(4) . ?
N1 C4 1.463(4) . ?
N2 C3 1.376(4) . ?
N2 C1 1.402(4) . ?
N2 C16 1.444(4) . ?
C2 C3 1.339(5) . ?
C2 H2 0.9500 . ?
C3 H3 0.9500 . ?
C4 C9 1.371(5) . ?
C4 C5 1.394(5) . ?
C5 C6 1.425(5) . ?
C5 C10 1.495(5) . ?
C6 C7 1.348(6) . ?
C6 H6 0.9500 . ?
C7 C8 1.364(6) . ?
C7 H7 0.9500 . ?
C8 C9 1.397(5) . ?
C8 H8 0.9500 . ?
C9 C13 1.524(5) . ?
C10 C11 1.516(6) . ?
C10 C12 1.518(6) . ?
C10 H10 1.0000 . ?
C11 H11A 0.9800 . ?
C11 H11B 0.9800 . ?
C11 H11C 0.9800 . ?
C12 H12A 0.9800 . ?
C12 H12B 0.9800 . ?
C12 H12C 0.9800 . ?
C13 C14 1.504(5) . ?
C13 C15 1.527(6) . ?
C13 H13 1.0000 . ?
C14 H14A 0.9800 . ?
C14 H14B 0.9800 . ?
C14 H14C 0.9800 . ?
C15 H15A 0.9800 . ?
C15 H15B 0.9800 . ?
C15 H15C 0.9800 . ?
C16 C21 1.385(5) . ?
C16 C17 1.394(5) . ?
C17 C18 1.391(5) . ?
C17 C22 1.505(5) . ?
C18 C19 1.373(5) . ?
C18 H18 0.9500 . ?
C19 C20 1.380(5) . ?
C19 H19 0.9500 . ?
C20 C21 1.415(5) . ?
C20 H20 0.9500 . ?
C21 C25 1.510(5) . ?
C22 C24 1.505(5) . ?
C22 C23 1.542(5) . ?
C22 H22 1.0000 . ?
C23 H23A 0.9800 . ?
C23 H23B 0.9800 . ?
C23 H23C 0.9800 . ?
C24 H24A 0.9800 . ?
C24 H24B 0.9800 . ?
C24 H24C 0.9800 . ?
C25 C26 1.493(6) . ?
C25 C27 1.532(5) . ?
C25 H25 1.0000 . ?
C26 H26A 0.9800 . ?
C26 H26B 0.9800 . ?
C26 H26C 0.9800 . ?
C27 H27A 0.9800 . ?
C27 H27B 0.9800 . ?
C27 H27C 0.9800 . ?

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
C1 Si Si 109.55(13) . 3_645 ?
C1 Si H 112.9 . . ?
Si Si H 70.7 3_645 . ?
C2 N1 C1 111.9(3) . . ?
C2 N1 C4 122.8(3) . . ?
C1 N1 C4 124.8(3) . . ?
C3 N2 C1 111.4(3) . . ?
C3 N2 C16 124.6(3) . . ?
C1 N2 C16 123.5(3) . . ?
N1 C1 N2 101.8(3) . . ?
N1 C1 Si 134.8(2) . . ?
N2 C1 Si 123.3(2) . . ?
C3 C2 N1 107.7(3) . . ?
C3 C2 H2 126.1 . . ?
N1 C2 H2 126.1 . . ?
C2 C3 N2 107.1(3) . . ?
C2 C3 H3 126.5 . . ?
N2 C3 H3 126.5 . . ?
C9 C4 C5 125.2(3) . . ?
C9 C4 N1 118.4(3) . . ?
C5 C4 N1 116.4(3) . . ?
C4 C5 C6 114.6(4) . . ?
C4 C5 C10 124.6(3) . . ?
C6 C5 C10 120.7(3) . . ?
C7 C6 C5 121.2(4) . . ?
C7 C6 H6 119.4 . . ?
C5 C6 H6 119.4 . . ?
C6 C7 C8 121.8(4) . . ?
C6 C7 H7 119.1 . . ?
C8 C7 H7 119.1 . . ?
C7 C8 C9 120.4(4) . . ?
C7 C8 H8 119.8 . . ?
C9 C8 H8 119.8 . . ?
C4 C9 C8 116.7(3) . . ?
C4 C9 C13 122.9(3) . . ?
C8 C9 C13 120.3(3) . . ?
C5 C10 C11 111.3(3) . . ?
C5 C10 C12 113.4(3) . . ?
C11 C10 C12 110.9(4) . . ?
C5 C10 H10 106.9 . . ?
C11 C10 H10 106.9 . . ?
C12 C10 H10 106.9 . . ?
C10 C11 H11A 109.5 . . ?
C10 C11 H11B 109.5 . . ?
H11A C11 H11B 109.5 . . ?
C10 C11 H11C 109.5 . . ?
H11A C11 H11C 109.5 . . ?
H11B C11 H11C 109.5 . . ?
C10 C12 H12A 109.5 . . ?
C10 C12 H12B 109.5 . . ?
H12A C12 H12B 109.5 . . ?
C10 C12 H12C 109.5 . . ?
H12A C12 H12C 109.5 . . ?
H12B C12 H12C 109.5 . . ?
C14 C13 C9 113.9(3) . . ?
C14 C13 C15 111.1(4) . . ?
C9 C13 C15 111.1(4) . . ?
C14 C13 H13 106.8 . . ?
C9 C13 H13 106.8 . . ?
C15 C13 H13 106.8 . . ?
C13 C14 H14A 109.5 . . ?
C13 C14 H14B 109.5 . . ?
H14A C14 H14B 109.5 . . ?
C13 C14 H14C 109.5 . . ?
H14A C14 H14C 109.5 . . ?
H14B C14 H14C 109.5 . . ?
C13 C15 H15A 109.5 . . ?
C13 C15 H15B 109.5 . . ?
H15A C15 H15B 109.5 . . ?
C13 C15 H15C 109.5 . . ?
H15A C15 H15C 109.5 . . ?
H15B C15 H15C 109.5 . . ?
C21 C16 C17 124.2(3) . . ?
C21 C16 N2 117.8(3) . . ?
C17 C16 N2 118.1(3) . . ?
C18 C17 C16 117.0(3) . . ?
C18 C17 C22 121.2(3) . . ?
C16 C17 C22 121.8(3) . . ?
C19 C18 C17 120.7(3) . . ?
C19 C18 H18 119.6 . . ?
C17 C18 H18 119.6 . . ?
C18 C19 C20 121.4(4) . . ?
C18 C19 H19 119.3 . . ?
C20 C19 H19 119.3 . . ?
C19 C20 C21 120.0(4) . . ?
C19 C20 H20 120.0 . . ?
C21 C20 H20 120.0 . . ?
C16 C21 C20 116.6(3) . . ?
C16 C21 C25 124.0(3) . . ?
C20 C21 C25 119.4(3) . . ?
C24 C22 C17 111.1(3) . . ?
C24 C22 C23 110.6(3) . . ?
C17 C22 C23 112.7(3) . . ?
C24 C22 H22 107.4 . . ?
C17 C22 H22 107.4 . . ?
C23 C22 H22 107.4 . . ?
C22 C23 H23A 109.5 . . ?
C22 C23 H23B 109.5 . . ?
H23A C23 H23B 109.5 . . ?
C22 C23 H23C 109.5 . . ?
H23A C23 H23C 109.5 . . ?
H23B C23 H23C 109.5 . . ?
C22 C24 H24A 109.5 . . ?
C22 C24 H24B 109.5 . . ?
H24A C24 H24B 109.5 . . ?
C22 C24 H24C 109.5 . . ?
H24A C24 H24C 109.5 . . ?
H24B C24 H24C 109.5 . . ?
C26 C25 C21 114.0(4) . . ?
C26 C25 C27 111.7(3) . . ?
C21 C25 C27 110.6(3) . . ?
C26 C25 H25 106.7 . . ?
C21 C25 H25 106.7 . . ?
C27 C25 H25 106.7 . . ?
C25 C26 H26A 109.5 . . ?
C25 C26 H26B 109.5 . . ?
H26A C26 H26B 109.5 . . ?
C25 C26 H26C 109.5 . . ?
H26A C26 H26C 109.5 . . ?
H26B C26 H26C 109.5 . . ?
C25 C27 H27A 109.5 . . ?
C25 C27 H27B 109.5 . . ?
H27A C27 H27B 109.5 . . ?
C25 C27 H27C 109.5 . . ?
H27A C27 H27C 109.5 . . ?
H27B C27 H27C 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
C2 N1 C1 N2 0.1(3) . . . . ?
C4 N1 C1 N2 -172.3(3) . . . . ?
C2 N1 C1 Si -175.7(3) . . . . ?
C4 N1 C1 Si 11.9(5) . . . . ?
C3 N2 C1 N1 -0.1(3) . . . . ?
C16 N2 C1 N1 171.9(3) . . . . ?
C3 N2 C1 Si 176.3(2) . . . . ?
C16 N2 C1 Si -11.7(4) . . . . ?
Si Si C1 N1 -1.6(4) 3_645 . . . ?
Si Si C1 N2 -176.7(2) 3_645 . . . ?
C1 N1 C2 C3 -0.1(4) . . . . ?
C4 N1 C2 C3 172.5(3) . . . . ?
N1 C2 C3 N2 0.0(4) . . . . ?
C1 N2 C3 C2 0.0(4) . . . . ?
C16 N2 C3 C2 -171.8(3) . . . . ?
C2 N1 C4 C9 -93.3(4) . . . . ?
C1 N1 C4 C9 78.3(4) . . . . ?
C2 N1 C4 C5 86.4(4) . . . . ?
C1 N1 C4 C5 -101.9(4) . . . . ?
C9 C4 C5 C6 1.9(6) . . . . ?
N1 C4 C5 C6 -177.9(3) . . . . ?
C9 C4 C5 C10 178.7(4) . . . . ?
N1 C4 C5 C10 -1.1(5) . . . . ?
C4 C5 C6 C7 -1.3(6) . . . . ?
C10 C5 C6 C7 -178.2(4) . . . . ?
C5 C6 C7 C8 1.3(7) . . . . ?
C6 C7 C8 C9 -1.8(7) . . . . ?
C5 C4 C9 C8 -2.4(5) . . . . ?
N1 C4 C9 C8 177.4(3) . . . . ?
C5 C4 C9 C13 179.7(3) . . . . ?
N1 C4 C9 C13 -0.6(5) . . . . ?
C7 C8 C9 C4 2.2(6) . . . . ?
C7 C8 C9 C13 -179.8(4) . . . . ?
C4 C5 C10 C11 -108.0(4) . . . . ?
C6 C5 C10 C11 68.7(5) . . . . ?
C4 C5 C10 C12 126.1(4) . . . . ?
C6 C5 C10 C12 -57.3(5) . . . . ?
C4 C9 C13 C14 -139.0(4) . . . . ?
C8 C9 C13 C14 43.1(5) . . . . ?
C4 C9 C13 C15 94.6(4) . . . . ?
C8 C9 C13 C15 -83.3(5) . . . . ?
C3 N2 C16 C21 82.4(4) . . . . ?
C1 N2 C16 C21 -88.5(4) . . . . ?
C3 N2 C16 C17 -96.8(4) . . . . ?
C1 N2 C16 C17 92.2(4) . . . . ?
C21 C16 C17 C18 1.0(5) . . . . ?
N2 C16 C17 C18 -179.8(3) . . . . ?
C21 C16 C17 C22 -177.5(3) . . . . ?
N2 C16 C17 C22 1.7(5) . . . . ?
C16 C17 C18 C19 -0.2(5) . . . . ?
C22 C17 C18 C19 178.3(3) . . . . ?
C17 C18 C19 C20 0.5(6) . . . . ?
C18 C19 C20 C21 -1.7(6) . . . . ?
C17 C16 C21 C20 -2.1(5) . . . . ?
N2 C16 C21 C20 178.7(3) . . . . ?
C17 C16 C21 C25 178.2(3) . . . . ?
N2 C16 C21 C25 -1.0(5) . . . . ?
C19 C20 C21 C16 2.3(5) . . . . ?
C19 C20 C21 C25 -177.9(4) . . . . ?
C18 C17 C22 C24 -84.0(4) . . . . ?
C16 C17 C22 C24 94.4(4) . . . . ?
C18 C17 C22 C23 40.8(5) . . . . ?
C16 C17 C22 C23 -140.8(3) . . . . ?
C16 C21 C25 C26 120.0(4) . . . . ?
C20 C21 C25 C26 -59.8(5) . . . . ?
C16 C21 C25 C27 -113.2(4) . . . . ?
C20 C21 C25 C27 67.0(5) . . . . ?

_refine_diff_density_max         0.461
_refine_diff_density_min         -0.272
_refine_diff_density_rms         0.073



