Redetermination of 5-iodouracil
Gustavo Portalone; Acta Crystallographica Section E 64 (2008) o365–o365; doi:10.1107/S1600536807068043

data_2217672
_publ_section_title
;
 Redetermination of 5-iodouracil
;
_journal_coeditor_code           TK2237
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o365
_journal_page_last               o365
_journal_paper_doi               10.1107/S1600536807068043
_journal_volume                  64
_journal_year                    2008
_chemical_formula_iupac          'C4 H3 I N2 O2'
_chemical_formula_moiety         'C4 H3 I N2 O2'
_chemical_formula_sum            'C4 H3 I N2 O2'
_chemical_formula_weight         237.98
_chemical_name_common            5-iodouracil
_chemical_name_systematic
;
2,4-dihydroxy-5-iodopyrimidine
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90
_cell_angle_beta                 92.341(2)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   4.89650(18)
_cell_length_b                   4.45921(13)
_cell_length_c                   14.2167(2)
_cell_measurement_reflns_used    29638
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      32.4
_cell_measurement_theta_min      2.9
_cell_volume                     310.156(15)
_computing_cell_refinement       'CrysAlis RED (Oxford Diffraction, 2006)'
_computing_data_collection       'CrysAlis CCD (Oxford Diffraction, 2006)'
_computing_data_reduction        'CrysAlis RED (Oxford Diffraction, 2006)'
_computing_molecular_graphics    'WinGX (Farrugia, 1999)'
_computing_publication_material  'WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare <i>et al.</i>,  1999)'
_diffrn_ambient_temperature      298(2)
_diffrn_detector_area_resol_mean 16.0696
_diffrn_measured_fraction_theta_full 0.966
_diffrn_measured_fraction_theta_max 0.966
_diffrn_measurement_device_type  'Oxford Diffraction Xcalibur S CCD'
_diffrn_measurement_method       '\w and \f'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.049
_diffrn_reflns_av_sigmaI/netI    0.014
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            48636
_diffrn_reflns_theta_full        32.4
_diffrn_reflns_theta_max         32.4
_diffrn_reflns_theta_min         2.9
_diffrn_standards_decay_%        1
_exptl_absorpt_coefficient_mu    5.083
_exptl_absorpt_correction_T_max  0.602
_exptl_absorpt_correction_T_min  0.252
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(CrysAlis RED; Oxford Diffraction, 2006),
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.548
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       tablets
_exptl_crystal_F_000             220
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.38
_refine_diff_density_min         -0.03
_refine_ls_abs_structure_details 'Flack (1983), 934 Friedel pairs'
_refine_ls_abs_structure_Flack   -0.01(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.04
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     86
_refine_ls_number_reflns         2127
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.04
_refine_ls_R_factor_all          0.029
_refine_ls_R_factor_gt           0.025
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0471P)^2^+0.0442P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.068
_refine_ls_wR_factor_ref         0.071
_reflns_number_gt                1803
_reflns_number_total             2127
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            tk2237.cif
_cod_data_source_block           I
_cod_original_cell_volume        310.157(15)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               2217672
_cod_database_fobs_code          2217672