5-Hydroxy-7,8,2'-trimethoxyflavone
Krishnaiah, M.; Ravi Kumar, R.; Jagadeesh Kumar, N.; Gunasekar, D.; Jayaprakasam, B.; Acta Crystallographica Section E 61 (2005) o2862–o2864; doi:10.1107/S1600536805024827

data_2206735
_publ_section_title
;
 5-Hydroxy-7,8,2'-trimethoxyflavone
;
_journal_coeditor_code           LH6457
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2862
_journal_page_last               o2864
_journal_paper_doi               10.1107/S1600536805024827
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C18 H16 O6'
_chemical_formula_moiety         'C18 H16 O6'
_chemical_formula_sum            'C18 H16 O6'
_chemical_formula_weight         328.31
_chemical_name_common            ' flavone'
_chemical_name_systematic        5-hydroxy-7,8,2'-trimethoxyflavone
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                85.252(16)
_cell_angle_beta                 84.838(12)
_cell_angle_gamma                78.469(14)
_cell_formula_units_Z            2
_cell_length_a                   7.602(2)
_cell_length_b                   8.7563(10)
_cell_length_c                   11.642(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    297(2)
_cell_measurement_theta_max      25
_cell_measurement_theta_min      2
_cell_volume                     754.6(3)
_computing_cell_refinement       'CAD-4 Software'
_computing_data_collection       'CAD-4 Software (Enraf--Nonius, 1989)'
_computing_data_reduction        'XCAD4 in WinGX (Farrugia, 1999)'
_computing_molecular_graphics    'ZORTEP in WinGX'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Enraf--Nonius CAD-4'
_diffrn_measurement_method       \w--2\q
_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  0.0058
_diffrn_reflns_av_sigmaI/netI    0.0101
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            2854
_diffrn_reflns_theta_full        25.0
_diffrn_reflns_theta_max         24.98
_diffrn_reflns_theta_min         2.38
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  60
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.109
_exptl_absorpt_correction_T_max  0.970
_exptl_absorpt_correction_T_min  0.950
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North et al., 1968)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.445
_exptl_crystal_density_meas      1.44
_exptl_crystal_density_method    KI-flotation
_exptl_crystal_description       rectangular
_exptl_crystal_F_000             344
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.171
_refine_diff_density_min         -0.127
_refine_ls_extinction_coef       0.121(7)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.068
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     282
_refine_ls_number_reflns         2635
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.068
_refine_ls_R_factor_all          0.0371
_refine_ls_R_factor_gt           0.0315
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0491P)^2^+0.1561P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0883
_refine_ls_wR_factor_ref         0.0941
_reflns_number_gt                2289
_reflns_number_total             2635
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            lh6457.cif
_cod_data_source_block           I
_cod_database_code               2206735
_cod_database_fobs_code          2206735