Tetrathiafulvalene with a fused pyrazine ring
Tomura, Masaaki; Yamashita, Yoshiro; Acta Crystallographica Section E 57 (2001) o307–o308; doi:10.1107/S1600536801003701

data_2200211
_publ_section_title
;
 Tetrathiafulvalene with a fused pyrazine ring
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o307
_journal_page_last               o308
_journal_paper_doi               10.1107/S1600536801003701
_journal_volume                  57
_journal_year                    2001
_chemical_formula_iupac          'C8 H4 N2 S4'
_chemical_formula_moiety         'C8 H4 N2 S4'
_chemical_formula_sum            'C8 H4 N2 S4'
_chemical_formula_weight         256.37
_chemical_melting_point          182
_chemical_name_common
;
pyrazinotetrathiafulvalene
;
_chemical_name_systematic
;
2-(1,3-dithiol-2-ylidene)-2,3-dihydro-1,3-dithia-4,7-diazaindene
;
_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'
_cell_angle_alpha                90.00
_cell_angle_beta                 96.89(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.481(2)
_cell_length_b                   9.1928(9)
_cell_length_c                   12.8980(14)
_cell_measurement_reflns_used    24
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      42.75
_cell_measurement_theta_min      9.66
_cell_volume                     998.3(3)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection       'CAD-4 EXPRESS (Enraf-Nonius, 1992)'
_computing_data_reduction        'HELENA (Spek, 1997)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full .996
_diffrn_measured_fraction_theta_max .996
_diffrn_measurement_device_type  'Enraf-Nonius CAD-4'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  .0841
_diffrn_reflns_av_sigmaI/netI    .1940
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            2060
_diffrn_reflns_theta_full        74.21
_diffrn_reflns_theta_max         74.21
_diffrn_reflns_theta_min         5.93
_diffrn_standards_decay_%        4.9
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    8.393
_exptl_absorpt_correction_T_max  .6790
_exptl_absorpt_correction_T_min  .1342
_exptl_absorpt_correction_type   '\y scan'
_exptl_absorpt_process_details   '(North et al., 1968)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.706
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             520
_exptl_crystal_size_max          .40
_exptl_crystal_size_mid          .05
_exptl_crystal_size_min          .05
_refine_diff_density_max         .472
_refine_diff_density_min         -.620
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.072
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     127
_refine_ls_number_reflns         2026
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.072
_refine_ls_R_factor_all          .2738
_refine_ls_R_factor_gt           .0794
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
calc w = 1/[\s^2^(Fo^2^)+(0.0473P)^2^] where P = (Fo^2^+2Fc^2^)/3
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .1984
_reflns_number_gt                663
_reflns_number_total             2026
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ob6031.cif
_cod_data_source_block           I
_cod_original_cell_volume        998.4(3)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2200211
_cod_database_fobs_code          2200211