Electron and Electrostatic Properties of Three Crystal Forms of Piracetam
Chambrier, Marie-Hélène; Bouhmaida, Nouzha; Bonhomme, François; Lebègue, Sébastien; Gillet, Jean-Michel; Jelsch, Christian; Ghermani, Nour Eddine; Crystal Growth & Design 11 (2011) 2528–; doi:10.1021/cg200291t

data_4500781
_publ_section_title
;
 Electron and Electrostatic Properties of Three Crystal Forms of Piracetam
;
_journal_issue                   6
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              2528
_journal_paper_doi               10.1021/cg200291t
_journal_volume                  11
_journal_year                    2011
_chemical_absolute_configuration -
_chemical_formula_moiety         'C6 H10 N2 O2'
_chemical_formula_sum            'C6 H10 N2 O2'
_chemical_formula_weight         142.150
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           MoPro
_cell_angle_alpha                90.00
_cell_angle_beta                 92.057(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.4539(5)
_cell_length_b                   6.3857(5)
_cell_length_c                   16.1814(10)
_cell_volume                     666.45(8)
_computing_structure_refinement  'MoPro (J. Appl. Cryst. 2005, 38, 38-54)'
_diffrn_measured_fraction_theta_full 0.962
_diffrn_measured_fraction_theta_max 0.875
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_sigmaI/netI    0.05458
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_theta_full        41.281
_diffrn_reflns_theta_max         52.64
_diffrn_reflns_theta_min         2.52
_exptl_crystal_density_diffrn    1.417
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             304
_refine_diff_density_max         0.32
_refine_diff_density_min         -0.30
_refine_diff_density_rms         0.056
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.012
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     133
_refine_ls_number_reflns         6830
_refine_ls_number_restraints     18
_refine_ls_restrained_S_all      2.365
_refine_ls_R_factor_all          0.0352
_refine_ls_R_factor_gt           0.0259
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef F
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_gt          0.0260
_refine_ls_wR_factor_ref         0.0273
_reflns_number_gt                5596
_reflns_number_total             6830
_reflns_threshold_expression     >2.0sigma(I)
_cod_data_source_file            cg200291t_si_002.cif
_cod_data_source_block           I
_cod_original_cell_volume        666.47(8)
_cod_original_sg_symbol_Hall     'P ?'
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               4500781