Contraction and Expansion of the Silicon Scaffold of Stable Si6R6 Isomers
Kai Abersfelder; Adam Russell; Henry S. Rzepa; Andrew J. P. White; Peter R. Haycock; David Scheschkewitz; Journal of the American Chemical Society 134 (2012) 16008–16016; doi:10.1021/ja307344f

data_4118686
_publ_section_title
;
 Contraction and Expansion of the Silicon Scaffold of Stable Si6R6 Isomers
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16008
_journal_page_last               16016
_journal_paper_doi               10.1021/ja307344f
_journal_volume                  134
_journal_year                    2012
_chemical_formula_moiety         'C120 H184 Si11, 1.25(C6 H14)'
_chemical_formula_sum            'C127.5 H201.5 Si11'
_chemical_formula_weight         2043.38
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 106.6533(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   24.30088(11)
_cell_length_b                   31.59551(13)
_cell_length_c                   35.05545(16)
_cell_measurement_reflns_used    117536
_cell_measurement_temperature    173
_cell_measurement_theta_max      72.3611
_cell_measurement_theta_min      1.8960
_cell_volume                     25786.6(2)
_computing_cell_refinement       'CrysAlis RED, Oxford Diffraction Ltd'
_computing_data_collection       'CrysAlis CCD, Oxford Diffraction Ltd'
_computing_data_reduction        'CrysAlis RED, Oxford Diffraction Ltd'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173
_diffrn_detector_area_resol_mean 8.2556
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type  'OD Xcalibur PX Ultra'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance Ultra (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0290
_diffrn_reflns_av_sigmaI/netI    0.0209
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       38
_diffrn_reflns_limit_k_min       -38
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -43
_diffrn_reflns_number            213833
_diffrn_reflns_theta_full        72.51
_diffrn_reflns_theta_max         72.51
_diffrn_reflns_theta_min         1.92
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    1.373
_exptl_absorpt_correction_T_max  0.791
_exptl_absorpt_correction_T_min  0.739
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
; 
CrysAlisPro, Oxford Diffraction Ltd., 
Version 1.171.34.44 (release 25-10-2010 CrysAlis171 .NET) 
(compiled Oct 25 2010,18:11:34) 
Analytical numeric absorption correction using a multifaceted crystal 
model based on expressions derived by R.C. Clark & J.S. Reid. 
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897) 
;
_exptl_crystal_colour            Orange
_exptl_crystal_density_diffrn    1.053
_exptl_crystal_description       'blocky needles'
_exptl_crystal_F_000             8964
_exptl_crystal_size_max          0.27
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.21
_refine_diff_density_max         0.902
_refine_diff_density_min         -0.751
_refine_diff_density_rms         0.057
_refine_ls_extinction_coef       0.000012(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     2720
_refine_ls_number_reflns         50461
_refine_ls_number_restraints     924
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0697
_refine_ls_R_factor_gt           0.0630
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0893P)^2^+24.0068P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1716
_refine_ls_wR_factor_ref         0.1767
_reflns_number_gt                44758
_reflns_number_total             50461
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja307344f_si_002_3.cif
_cod_data_source_block           9
_cod_original_formula_sum        'C127.50 H201.50 Si11'
_cod_database_code               4118686