N—H···S and N—H···O hydrogen bonds: `pure' and `mixed' <i>R</i>^2^~2~(8) patterns in the crystal structures of eight 2-thiouracil derivatives
Hützler, Wilhelm Maximilian; Egert, Ernst; Acta Crystallographica Section C 70 (2014) 241–249; doi:10.1107/S2053229614001387

data_2019375
_publ_section_title
;
 N---H&#x00B7;&#x00B7;&#x00B7;S and N---H&#x00B7;&#x00B7;&#x00B7;O
 hydrogen bonds: `pure' and `mixed' <i>R</i>^2^~2~(8) patterns in the
 crystal structures of eight 2-thiouracil derivatives
;
_journal_coeditor_code           EG3147
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              241
_journal_page_last               249
_journal_paper_doi               10.1107/S2053229614001387
_journal_volume                  70
_journal_year                    2014
_chemical_formula_iupac          'C6 H8 N2 O S'
_chemical_formula_moiety         'C6 H8 N2 O S'
_chemical_formula_sum            'C6 H8 N2 O S'
_chemical_formula_weight         156.20
_chemical_name_systematic
;
5,6-Dimethyl-2-thiouracil
;
_space_group_IT_number           14
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_symmetry_space_group_name_Hall  '-P 2ybc'
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_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 112.336(11)
_cell_angle_gamma                90.00
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_cell_length_b                   15.2624(18)
_cell_length_c                   7.0948(11)
_cell_measurement_reflns_used    12075
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      26.05
_cell_measurement_theta_min      3.38
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_computing_cell_refinement       'X-AREA (Stoe & Cie, 2001)'
_computing_data_collection       'X-AREA (Stoe & Cie, 2001)'
_computing_data_reduction        'X-AREA (Stoe & Cie, 2001)'
_computing_molecular_graphics
;
Mercury (Macrae <i>et al.</i>, 2008) and XP in SHELXTL-Plus (Sheldrick,
2008)
;
_computing_publication_material  'publCIF (Westrip, 2010)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.988
_diffrn_measurement_device_type  'Stoe IPDS II two-circle diffractometer'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  'Genix 3D multilayer optics'
_diffrn_radiation_source         'Genix 3D I\mS microfocus X-ray source'
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_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0827
_diffrn_reflns_av_sigmaI/netI    0.0454
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            5187
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.65
_diffrn_reflns_theta_min         3.38
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.396
_exptl_absorpt_correction_T_max  0.9249
_exptl_absorpt_correction_T_min  0.8265
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(X-AREA; Stoe & Cie, 2001)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.517
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             328
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.284
_refine_diff_density_min         -0.325
_refine_ls_extinction_coef       0.060(17)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 2008)'
_refine_ls_goodness_of_fit_ref   1.067
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     102
_refine_ls_number_reflns         1285
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.067
_refine_ls_R_factor_all          0.0587
_refine_ls_R_factor_gt           0.0568
_refine_ls_shift/su_max          0.014
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0769P)^2^+0.3580P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1466
_refine_ls_wR_factor_ref         0.1487
_reflns_number_gt                1212
_reflns_number_total             1285
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            eg3147sup1.cif
_cod_data_source_block           III
_cod_original_cell_volume        684.04(17)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2019375