Barbiturates with hydrogen-bonded layer and framework structures
Gelbrich, Thomas; Rossi, Denise; Häfele, Clemens A.; Griesser, Ulrich J.; CrystEngComm 13 (2011) 5502–; doi:10.1039/c1ce05430a

data_7206422
_publ_section_title
;
 Barbiturates with hydrogen-bonded layer and framework structures
;
_journal_issue                   17
_journal_name_full               CrystEngComm
_journal_page_first              5502
_journal_paper_doi               10.1039/c1ce05430a
_journal_volume                  13
_journal_year                    2011
_chemical_formula_moiety         'C4 H2 Br2 N2 O3'
_chemical_formula_sum            'C4 H2 Br2 N2 O3'
_chemical_formula_weight         285.90
_chemical_melting_point          513
_chemical_name_systematic
;
5,5-dibromorobarbituric acid
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            24
_cell_length_a                   11.4204(2)
_cell_length_b                   12.9897(3)
_cell_length_c                   30.0304(8)
_cell_measurement_reflns_used    32764
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      26.02
_cell_measurement_theta_min      2.91
_cell_volume                     4454.94(18)
_computing_cell_refinement
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_data_collection       'COLLECT (Hooft, R.W.W., 1998)'
_computing_data_reduction
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type
'Bruker-Nonius APEX II CCD camera on \k-goniostat'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  '10cm confocal mirrors'
_diffrn_radiation_source         'Bruker-Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0667
_diffrn_reflns_av_sigmaI/netI    0.0539
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -35
_diffrn_reflns_number            21160
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.05
_diffrn_reflns_theta_min         3.14
_exptl_absorpt_coefficient_mu    10.874
_exptl_absorpt_correction_T_max  0.6124
_exptl_absorpt_correction_T_min  0.4094
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2007/2 (Sheldrick, G.M., 2007)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.558
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       platelet
_exptl_crystal_F_000             3216
_exptl_crystal_size_max          0.10
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.808
_refine_diff_density_min         -0.778
_refine_diff_density_rms         0.202
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.006
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     298
_refine_ls_number_reflns         3898
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.005
_refine_ls_R_factor_all          0.0742
_refine_ls_R_factor_gt           0.0519
_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^)+(0.0152P)^2^+93.5968P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0991
_refine_ls_wR_factor_ref         0.1078
_reflns_number_gt                3103
_reflns_number_total             3895
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1ce05430a.txt
_cod_data_source_block           3a
_cod_original_sg_symbol_H-M      Pbca
_cod_database_code               7206422