Chromium(IV) Siloxide
Michael P. Marshak; Daniel G. Nocera; Inorganic Chemistry 52 (2013) 1173–1175; doi:10.1021/ic3023612

data_4333731
_publ_section_title
;
 Chromium(IV) Siloxide
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              1173
_journal_page_last               1175
_journal_paper_doi               10.1021/ic3023612
_journal_volume                  52
_journal_year                    2013
_chemical_formula_moiety         'C36 H84 Cr O4 Si4'
_chemical_formula_sum            'C36 H84 Cr O4 Si4'
_chemical_formula_weight         745.39
_chemical_name_common            (disilox)4Cr
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 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                 118.9420(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   22.888(2)
_cell_length_b                   10.9647(9)
_cell_length_c                   20.834(3)
_cell_measurement_temperature    296(2)
_cell_volume                     4575.5(9)
_computing_cell_refinement       'SAINT 7.46A (Bruker-AXS, 2009)'
_computing_data_collection       'APEX2 v2009.9.0 (Bruker-AXS, 2009)'
_computing_data_reduction        'SAINT 7.46A (Bruker-AXS, 2009)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2009)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2009)'
_diffrn_ambient_temperature      296(2)
_diffrn_detector_area_resol_mean 8.3
_diffrn_measured_fraction_theta_full 0.946
_diffrn_measured_fraction_theta_max 0.946
_diffrn_measurement_device_type  'Bruker Smart APEX CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0376
_diffrn_reflns_av_sigmaI/netI    0.0232
_diffrn_reflns_limit_h_max       31
_diffrn_reflns_limit_h_min       -33
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            52150
_diffrn_reflns_theta_full        31.56
_diffrn_reflns_theta_max         31.56
_diffrn_reflns_theta_min         2.03
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.386
_exptl_absorpt_correction_T_max  0.9885
_exptl_absorpt_correction_T_min  0.8609
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 2009)'
_exptl_crystal_colour            brown
_exptl_crystal_density_diffrn    1.082
_exptl_crystal_description       plate
_exptl_crystal_F_000             1648
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.582
_refine_diff_density_min         -0.459
_refine_diff_density_rms         0.057
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.074
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     301
_refine_ls_number_reflns         7249
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.074
_refine_ls_R_factor_all          0.0432
_refine_ls_R_factor_gt           0.0321
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0407P)^2^+2.6703P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0799
_refine_ls_wR_factor_ref         0.0877
_reflns_number_gt                6098
_reflns_number_total             7249
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic3023612_si_002_2.cif
_cod_data_source_block           10078
_cod_original_cell_volume        4575.6(8)
_cod_database_code               4333731