Four polymorphs (polytypes) of 5,6-dimethylbenzofurazan 1-oxide
Britton, Doyle; Young, Jr, Victor G.; Noland, Wayland E.; Pinnow, Matthew J.; Clark, Christopher M.; Acta Crystallographica Section B 68 (2012) 536–542; doi:10.1107/S0108768112037457

data_2105257
_publ_section_title
;
 Four polymorphs (polytypes) of 5,6-dimethylbenzofurazan 1-oxide
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              536
_journal_page_last               542
_journal_paper_doi               10.1107/S0108768112037457
_journal_volume                  68
_journal_year                    2012
_chemical_formula_moiety         'C8 H8 N2 O2'
_chemical_formula_sum            'C8 H8 N2 O2'
_chemical_formula_weight         164.16
_chemical_name_systematic
;
 5,6-benzfurazan 1-oxide, polymorph Z4
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXTL
_cell_angle_alpha                89.264(2)
_cell_angle_beta                 83.419(2)
_cell_angle_gamma                87.027(2)
_cell_formula_units_Z            4
_cell_length_a                   7.3643(9)
_cell_length_b                   9.0332(11)
_cell_length_c                   11.6675(14)
_cell_measurement_reflns_used    3327
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      27.3
_cell_measurement_theta_min      2.8
_cell_volume                     769.99(16)
_computing_cell_refinement       'SAINT (Bruker, 2003)'
_computing_data_collection       'SMART (Bruker, 2003)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    SHELXTL
_computing_publication_material  SHELXTL
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 2008)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type
;
Bruker SMART 1K CCD area-detector diffractometer
;
_diffrn_measurement_method       '\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  0.0242
_diffrn_reflns_av_sigmaI/netI    0.0254
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            8977
_diffrn_reflns_theta_full        27.52
_diffrn_reflns_theta_max         27.52
_diffrn_reflns_theta_min         1.76
_diffrn_standards_decay_%        <1
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.105
_exptl_absorpt_correction_T_max  0.97
_exptl_absorpt_correction_T_min  0.96
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS; Sheldrick, 2008; Blessing, 1995
;
_exptl_crystal_colour            'pale yellow'
_exptl_crystal_density_diffrn    1.416
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             344
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.185
_refine_diff_density_min         -0.147
_refine_ls_extinction_coef       0.007(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXTL
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     304
_refine_ls_number_reflns         3498
_refine_ls_number_restraints     192
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0818
_refine_ls_R_factor_gt           0.0486
_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^)+(0.0710P)^2^+0.0760P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1251
_refine_ls_wR_factor_ref         0.1396
_reflns_number_gt                2286
_reflns_number_total             3498
_reflns_threshold_expression     '>2\s(I) '
_cod_data_source_file            ps5015.cif
_cod_data_source_block           Z4
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               2105257
_cod_database_fobs_code          2105257