Photodimerization of chromone.
Sakamoto, Masami; Kanehiro, Masayuki; Mino, Takashi; Fujita, Tsutomu; Chemical communications (Cambridge, England) 34 (2009) 2379–2380; doi:10.1039/b822829a

data_7104363
_publ_section_title
;
 Photodimerization of chromone.
;
_journal_issue                   17
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              2379
_journal_page_last               2380
_journal_paper_doi               10.1039/b822829a
_journal_volume                  34
_journal_year                    2009
_chemical_formula_sum            'C18 H12 O4'
_chemical_formula_weight         292.28
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 98.247(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.5496(13)
_cell_length_b                   8.5832(10)
_cell_length_c                   14.7098(18)
_cell_measurement_reflns_used    2489
_cell_measurement_temperature    173
_cell_measurement_theta_max      27.57
_cell_measurement_theta_min      2.75
_cell_volume                     1318.2(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173
_diffrn_detector_area_resol_mean 8.333
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.917
_diffrn_measurement_device_type  'APEX II CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            7195
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         28.42
_diffrn_reflns_theta_min         1.95
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.105
_exptl_absorpt_correction_T_max  0.9845
_exptl_absorpt_correction_T_min  0.9545
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS Sheldrick 1996'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.473
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             608
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.25
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_refine_ls_matrix_type           full
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_refine_ls_number_reflns         3043
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_refine_ls_restrained_S_all      1.058
_refine_ls_R_factor_all          0.0603
_refine_ls_R_factor_gt           0.0477
_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^)+(0.0617P)^2^+0.5416P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1260
_refine_ls_wR_factor_ref         0.1332
_reflns_number_gt                2411
_reflns_number_total             3043
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b822829a.txt
_cod_data_source_block           saka98_p21c
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7104363