2-Amino-5-trifluoromethyl-1,3,4-thiadiazole and a redetermination of 2-amino-1,3,4-thiadiazole, both at 120K: chains of edge-fused <i>R</i>~2~^2^(8) and <i>R</i>~4~^4^(10) rings, and sheets of <i>R</i>~2~^2^(8) and <i>R</i>~6~^6^(20) rings
Boechat, Nubia; Ferreira, Sabrina B.; Glidewell, Christopher; Low, John N.; Skakle, Janet M. S.; Wardell, Solange M. S. V.; Acta Crystallographica Section C 62 (2006) o42–o44; doi:10.1107/S0108270105040126

data_2014395
_publ_section_title
;
 2-Amino-5-trifluoromethyl-1,3,4-thiadiazole and a redetermination of
 2-amino-1,3,4-thiadiazole, both at 120K: chains of edge-fused
 <i>R</i>~2~^2^(8) and <i>R</i>~4~^4^(10) rings, and sheets of
 <i>R</i>~2~^2^(8) and <i>R</i>~6~^6^(20) rings
;
_journal_coeditor_code           SK1892
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o42
_journal_page_last               o44
_journal_paper_doi               10.1107/S0108270105040126
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C2 H3 N3 S'
_chemical_formula_moiety         'C2 H3 N3 S'
_chemical_formula_sum            'C2 H3 N3 S'
_chemical_formula_weight         101.13
_chemical_name_systematic
;
2-amino-1,3,4-thiadiazole
;
_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'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 109.984(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.5718(5)
_cell_length_b                   13.4573(17)
_cell_length_c                   5.7875(5)
_cell_measurement_reflns_used    936
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      27.63
_cell_measurement_theta_min      3.03
_cell_volume                     407.83(7)
_computing_cell_refinement       'DENZO (Otwinowski & Minor, 1997) and COLLECT'
_computing_data_collection       'COLLECT (Nonius, 1999)'
_computing_data_reduction        'DENZO and COLLECT'
_computing_molecular_graphics    'PLATON (Spek, 2003)'
_computing_publication_material  'SHELXL97 and PRPKAPPA (Ferguson, 1999)'
_computing_structure_refinement
'OSCAIL (McArdle, 2003) and SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution
'WinGX (Farrugia, 1999) and SIR92 (Altomare <i>et al.</i>,  1993)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 9.091
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.985
_diffrn_measurement_device_type  'Nonius KappaCCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Bruker Nonius FR91 rotating anode'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0962
_diffrn_reflns_av_sigmaI/netI    0.0580
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            6842
_diffrn_reflns_theta_full        26.50
_diffrn_reflns_theta_max         27.63
_diffrn_reflns_theta_min         3.03
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.604
_exptl_absorpt_correction_T_max  0.988
_exptl_absorpt_correction_T_min  0.919
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick,  2003)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.647
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             208
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.04
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.393
_refine_diff_density_min         -0.375
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.078
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     59
_refine_ls_number_reflns         936
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.078
_refine_ls_R_factor_all          0.0656
_refine_ls_R_factor_gt           0.0384
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.056P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0935
_refine_ls_wR_factor_ref         0.1020
_reflns_number_gt                736
_reflns_number_total             936
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sk1892.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2014395
_cod_database_fobs_code          2014395