Synthesis, structures and optical properties of trisilasumanene and its related compounds.
Tanikawa, Tomoharu; Saito, Masaichi; Guo, Jing Dong; Nagase, Shigeru; Organic & biomolecular chemistry 9 (2011) 1731–1735; doi:10.1039/C0OB00987C

data_7151725
_publ_section_title
;
 Synthesis, structures and optical properties of trisilasumanene and
 its related compounds.
;
_journal_issue                   6
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1731
_journal_page_last               1735
_journal_paper_doi               10.1039/C0OB00987C
_journal_volume                  9
_journal_year                    2011
_chemical_formula_moiety         'C20 H16 Si'
_chemical_formula_sum            'C20 H16 Si'
_chemical_formula_weight         284.42
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.3831(10)
_cell_length_b                   11.7677(15)
_cell_length_c                   15.0120(19)
_cell_measurement_reflns_used    6063
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.91
_cell_measurement_theta_min      2.71
_cell_volume                     1480.9(3)
_computing_cell_refinement       'Bruker SMART (Bruker 2000)'
_computing_data_collection       'Bruker SMART (Bruker 2000)'
_computing_data_reduction        'Bruker SAINT (Bruker 2000)'
_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      100(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0248
_diffrn_reflns_av_sigmaI/netI    0.0263
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            10647
_diffrn_reflns_theta_full        27.93
_diffrn_reflns_theta_max         27.93
_diffrn_reflns_theta_min         2.20
_exptl_absorpt_coefficient_mu    0.149
_exptl_absorpt_correction_T_max  0.956
_exptl_absorpt_correction_T_min  0.931
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
SADABS; Sheldrick 1996
;
_exptl_crystal_density_diffrn    1.276
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             600
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.536
_refine_diff_density_min         -0.284
_refine_diff_density_rms         0.059
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.04(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.057
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     192
_refine_ls_number_reflns         3549
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.057
_refine_ls_R_factor_all          0.0406
_refine_ls_R_factor_gt           0.0381
_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^)+(0.0670P)^2^+0.1754P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0978
_refine_ls_wR_factor_ref         0.1005
_reflns_number_gt                3356
_reflns_number_total             3549
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            C0OB00987C.TXT
_cod_data_source_block           masa442
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1555 2011-01-17 13:19:09Z saulius 
;
_cod_original_sg_symbol_Hall     'P 2ac 2ab '
_cod_database_code               7151725