1,4-Dibromo-1,4-disilabutane
Mitzel, N. W.; Riede, J.; Schmidbaur, H.; Acta Crystallographica Section C 52 (1996) 980–982; doi:10.1107/S010827019501451X

data_2004707
_publ_section_title
;
 1,4-Dibromo-1,4-disilabutane
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              980
_journal_page_last               982
_journal_paper_doi               10.1107/S010827019501451X
_journal_volume                  52
_journal_year                    1996
_chemical_formula_sum            'C2 H8 Br2 Si2'
_chemical_formula_weight         248.08
_chemical_name_systematic
;
1,4-Dibromo-1,4-disilabutane
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.1040(10)
_cell_length_b                   9.9750(10)
_cell_length_c                   9.986(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    195(3)
_cell_measurement_theta_max      19
_cell_measurement_theta_min      15
_cell_volume                     807.2(2)
_computing_cell_refinement       'CAD4 Software'
_computing_data_collection       'CAD4 Software (Enraf-Nonius, 1989)'
_computing_data_reduction        'local programs'
_computing_molecular_graphics    'SHELXTL-Plus (Sheldrick, 1989)'
_computing_publication_material  SHELXL-93
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      195(3)
_diffrn_measurement_device       'Enraf-Nonius CAD4 diffractometer'
_diffrn_measurement_method
;
\w-\q scans with \w scan width (1.0 + 0.35 tan\q)\%
;
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  '0.202 (on 4 reflections only)'
_diffrn_reflns_av_sigmaI/netI    0.0236
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            884
_diffrn_reflns_theta_max         26.96
_diffrn_reflns_theta_min         3.83
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    10.231
_exptl_absorpt_correction_T_max  0.039
_exptl_absorpt_correction_T_min  0.016
_exptl_absorpt_correction_type
;
empirical, \y scans (North, Philips & Matthews, 1968) and \DF (DIFABS;
Walker & Stuart, 1983)
;
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    2.041
_exptl_crystal_description       block
_exptl_crystal_F_000             472
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.30
_refine_diff_density_max         0.446
_refine_diff_density_min         -0.437
_refine_ls_extinction_coef       0.0009(4)
_refine_ls_extinction_method     'SHELXL93 (Sheldrick, 1993)'
_refine_ls_goodness_of_fit_all   1.168
_refine_ls_goodness_of_fit_obs   1.243
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     45
_refine_ls_number_reflns         876
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.270
_refine_ls_restrained_S_obs      1.243
_refine_ls_R_factor_all          0.0485
_refine_ls_R_factor_obs          0.0315
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0357P)^2^+0.1370P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0779
_refine_ls_wR_factor_obs         0.0676
_reflns_number_observed          699
_reflns_number_total             880
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            cf1041.cif
_cod_data_source_block           brom
_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 1527 2010-12-29 10:47:43Z saulius 

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_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0357P)^2^+0.1370P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
1/[\s^2^(Fo^2^)+(0.0357P)^2^+0.1370P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               2004707