Hydrogen atom behaviour imaged in a short intramolecular hydrogen bond using the combined approach of X-ray and neutron diffraction
Thomas, Lynne H.; Florence, Alastair J.; Wilson, Chick C.; New Journal of Chemistry 33 (2009) 2486–; doi:10.1039/b908915b

data_7053831
_publ_section_title
;
 Hydrogen atom behaviour imaged in a short intramolecular hydrogen bond
 using the combined approach of X-ray and neutron diffraction
;
_journal_issue                   12
_journal_name_full               'New Journal of Chemistry'
_journal_page_first              2486
_journal_paper_doi               10.1039/b908915b
_journal_volume                  33
_journal_year                    2009
_chemical_formula_sum            'C15 H12 O2'
_chemical_formula_weight         224.25
_chemical_name_systematic
;
dibenzoylmethane
;
_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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2009-03-29T18:08:06-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   8.7228(10)
_cell_length_b                   10.7969(12)
_cell_length_c                   24.423(3)
_cell_measurement_reflns_used    2800
_cell_measurement_temperature    240(2)
_cell_measurement_theta_max      118.18
_cell_measurement_theta_min      13.05
_cell_volume                     2300.1(5)
_computing_cell_refinement       'CrystalClear 1.4.0 (Rigaku, 2008)'
_computing_data_collection       'CrystalClear 1.4.0 (Rigaku, 2008)'
_computing_data_reduction        'CrystalClear 1.4.0 (Rigaku, 2008)'
_computing_molecular_graphics
'ORTEP (Farrugia, 1997), Mercury (McRae, 2006)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      240(2)
_diffrn_measured_fraction_theta_full 0.956
_diffrn_measured_fraction_theta_max 0.956
_diffrn_measurement_device_type
;
'Rigaku R-AXIS RAPID IP Image Plate diffractometer'
;
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54186
_diffrn_reflns_av_R_equivalents  0.0261
_diffrn_reflns_av_unetI/netI     0.0258
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            9247
_diffrn_reflns_theta_full        71.86
_diffrn_reflns_theta_max         71.86
_diffrn_reflns_theta_min         6.77
_exptl_absorpt_coefficient_mu    0.683
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.295
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             944
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.177
_refine_diff_density_min         -0.152
_refine_diff_density_rms         0.035
_refine_ls_extinction_coef       0.00287(17)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.130
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     203
_refine_ls_number_reflns         2154
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.130
_refine_ls_R_factor_all          0.0619
_refine_ls_R_factor_gt           0.0382
_refine_ls_shift/su_max          0
_refine_ls_shift/su_mean         0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0217P)^2^+0.7097P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0746
_refine_ls_wR_factor_ref         0.0938
_reflns_number_gt                1477
_reflns_number_total             2154
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b908915bsup1.cif
_cod_data_source_block           dbm240_cu
_cod_original_cell_volume        2300.2(5)
_cod_original_sg_symbol_H-M      Pbca
_cod_database_code               7053831