Diffuse scattering study of aspirin forms (I) and (II)
Chan, E. J.; Welberry, T. R.; Heerdegen, A. P.; Goossens, D. J.; Acta Crystallographica Section B 66 (2010) 696–707; doi:10.1107/S0108768110037055

data_2104857
_publ_section_title
;
 Diffuse scattering study of aspirin forms (I) and (II)
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              696
_journal_page_last               707
_journal_paper_doi               10.1107/S0108768110037055
_journal_volume                  66
_journal_year                    2010
_chemical_formula_moiety         'C9 H8 O4'
_chemical_formula_sum            'C9 H8 O4'
_chemical_formula_weight         180.15
_chemical_name_common            aspirin
_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                 68.163(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.2696(5)
_cell_length_b                   6.5575(3)
_cell_length_c                   11.4960(4)
_cell_measurement_reflns_used    8462
_cell_measurement_temperature    300(2)
_cell_measurement_theta_max      2.546
_cell_measurement_theta_min      27.485
_cell_volume                     858.58(6)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_reduction
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'XTAL3.7 (Hall et al., 2001)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    known
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type  KappaCCD
_diffrn_measurement_method       CCD
_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  0.0312
_diffrn_reflns_av_sigmaI/netI    0.0296
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            6924
_diffrn_reflns_theta_full        27.20
_diffrn_reflns_theta_max         27.20
_diffrn_reflns_theta_min         3.59
_diffrn_standards_interval_count 0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.111
_exptl_absorpt_correction_T_max  0.9863
_exptl_absorpt_correction_T_min  0.9675
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details
;
Gaussian integration (Coppens, 1970)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.394
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             376
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.229
_refine_diff_density_min         -0.199
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.094
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     119
_refine_ls_number_reflns         1853
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.094
_refine_ls_R_factor_all          0.0580
_refine_ls_R_factor_gt           0.0429
_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^)+(0.0650P)^2^+0.1270P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1178
_refine_ls_wR_factor_ref         0.1291
_reflns_number_gt                1425
_reflns_number_total             1853
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            so5043.cif
_cod_data_source_block           aspirin-form2
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2104857