2,4-Dibromo-1,3-dihydroxy-9<i>H</i>-xanthen-9-one
Huang, Shi-Wen; Yang, Zheng-Min; Huang, Fu-Ping; Qin, Jiang-Ke; Acta Crystallographica Section E 69 (2013) o1361–; doi:10.1107/S1600536813019296

data_2238313
_publ_section_title
;
 2,4-Dibromo-1,3-dihydroxy-9<i>H</i>-xanthen-9-one
;
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1361
_journal_paper_doi               10.1107/S1600536813019296
_journal_volume                  69
_journal_year                    2013
_chemical_formula_iupac          'C13 H6 Br2 O4'
_chemical_formula_moiety         'C13 H6 Br2 O4'
_chemical_formula_sum            'C13 H6 Br2 O4'
_chemical_formula_weight         386.00
_chemical_name_systematic
;
2,4-Dibromo-1,3-dihydroxy-9<i>H</i>-xanthen-9-one
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.4489(15)
_cell_length_b                   16.9049(13)
_cell_length_c                   3.8564(3)
_cell_measurement_reflns_used    2778
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      26.158
_cell_measurement_theta_min      3.269
_cell_volume                     1202.72(16)
_computing_cell_refinement       'SAINT (Bruker, 1998)'
_computing_data_collection       'SMART (Bruker, 1998)'
_computing_data_reduction        'SAINT (Bruker, 1998)'
_computing_molecular_graphics    'SHELXL97 (Sheldrick, 2008)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker SMART CCD'
_diffrn_measurement_method       '\f and \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  0.0759
_diffrn_reflns_av_sigmaI/netI    0.0616
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -4
_diffrn_reflns_number            6188
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.63
_exptl_absorpt_coefficient_mu    6.746
_exptl_absorpt_correction_T_max  0.6877
_exptl_absorpt_correction_T_min  0.2539
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 1998)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    2.132
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             744
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.425
_refine_diff_density_min         -0.332
_refine_ls_abs_structure_details 'Flack (1983), 881 Friedel pairs'
_refine_ls_abs_structure_Flack   -0.008(16)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.039
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_constraints    0
_refine_ls_number_parameters     172
_refine_ls_number_reflns         2120
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.038
_refine_ls_R_factor_all          0.0435
_refine_ls_R_factor_gt           0.0344
_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^)+(0.0232P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0675
_refine_ls_wR_factor_ref         0.0696
_reflns_number_gt                1830
_reflns_number_total             2120
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bh2480.cif
_cod_data_source_block           I
_cod_database_code               2238313
_cod_database_fobs_code          2238313