4,4'-Dimethyl-1,1'-bi(1,2,3,5-diselenadiazole)
Bryan, C. D.; Cordes, A. W.; Oakley, R. T.; von Spence, R. E.; Acta Crystallographica Section C 51 (1995) 2402–2404; doi:10.1107/S0108270195006147

data_2004095
_publ_section_title
;
 4,4'-Dimethyl-1,1'-bi(1,2,3,5-diselenadiazole)
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2402
_journal_page_last               2404
_journal_paper_doi               10.1107/S0108270195006147
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C4 H6 N4 Se4 '
_chemical_formula_sum            'C4 H6 N4 Se4'
_chemical_formula_weight         425.96
_chemical_name_systematic
;
4-methyl-1,2,3,5-diselenadiazolyl
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_cell_angle_alpha                102.11(2)
_cell_angle_beta                 89.77(2)
_cell_angle_gamma                104.65(2)
_cell_formula_units_Z            4
_cell_length_a                   8.6495(14)
_cell_length_b                   9.857(2)
_cell_length_c                   12.375(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293
_cell_measurement_theta_max      12.00
_cell_measurement_theta_min      8.00
_cell_volume                     996.7(4)
_computing_cell_refinement       CAD-4--PC
_computing_data_collection       'CAD-4--PC (Enraf-Nonius, 1993)'
_computing_data_reduction
;
 NRCVAX (Gabe, Le Page, Charland, Lee & White, 1989)
;
_computing_molecular_graphics    NRCVAX
_computing_publication_material  'NRCVAX TABLES (Version of Jan 94)'
_computing_structure_refinement  NRCVAX
_computing_structure_solution    NRCVAX
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Enraf-Nonius CAD-4'
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'xray tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.045
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            3712
_diffrn_reflns_theta_max         24.92
_diffrn_reflns_theta_min         2.00
_diffrn_standards_decay_%        1.4
_diffrn_standards_interval_time  60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    14.5
_exptl_absorpt_correction_T_max  0.99
_exptl_absorpt_correction_T_min  0.40
_exptl_absorpt_correction_type   'empirical via \y scans of 3 reflections'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    2.84
_exptl_crystal_description       'thin needle'
_exptl_crystal_F_000             774.42
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.07
_refine_diff_density_max         1.14
_refine_diff_density_min         -0.98
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_obs   0.98
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     137
_refine_ls_number_reflns         1803
_refine_ls_R_factor_all          0.133
_refine_ls_R_factor_obs          0.047
_refine_ls_shift/esd_max         0.000
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/[\s^2^(F) + 0.0025F^2^]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.081
_refine_ls_wR_factor_obs         0.064
_reflns_number_observed          1803
_reflns_number_total             3493
_reflns_observed_criterion       'I~net~ > 3.0\s(I~net~)'
_cod_data_source_file            bk1120.cif
_cod_data_source_block           structure
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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 'Triclinic' changed to 'triclinic'
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 'w = 1/[\s^2^(F) + 0.0025F^2^]'
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^(F) +
0.0025F^2^]'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_formula_sum        'C4 H6 N4 Se4 '
_cod_database_code               2004095