Supramolecular constructs and thermodynamic stability of four polymorphs and a co-crystal of pentobarbital (nembutal)
Rossi, Denise; Gelbrich, Thomas; Kahlenberg, Volker; Griesser, Ulrich J.; CrystEngComm 14 (2012) 2494–; doi:10.1039/c2ce06659a

data_7207654
_publ_section_title
;
 Supramolecular constructs and thermodynamic stability of four polymorphs
 and a co-crystal of pentobarbital (nembutal)
;
_journal_issue                   7
_journal_name_full               CrystEngComm
_journal_page_first              2494
_journal_paper_doi               10.1039/c2ce06659a
_journal_volume                  14
_journal_year                    2012
_chemical_formula_sum            'C11 H18 N2 O3'
_chemical_formula_weight         226.27
_chemical_name_common            'pentobarbital, nembutal'
_chemical_name_systematic
;

5-ethyl,5-(1-methylbutyl)barbituric acid
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.7545(15)
_cell_length_b                   9.8660(8)
_cell_length_c                   7.1799(5)
_cell_measurement_reflns_used    12496
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      26.02
_cell_measurement_theta_min      2.91
_cell_volume                     1186.84(17)
_computing_cell_refinement
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_data_collection       'COLLECT (Hooft, R.W.W., 1998)'
_computing_data_reduction
'DENZO (Otwinowski & Minor, 1997) & COLLECT (Hooft, R.W.W., 1998)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean '4096x4096pixels / 62x62mm'
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type
;
Bruker-Nonius APEX II CCD camera on \k-goniostat
;
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  '10cm confocal mirrors'
_diffrn_radiation_source         'Bruker-Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0716
_diffrn_reflns_av_sigmaI/netI    0.0707
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            6337
_diffrn_reflns_theta_full        25.05
_diffrn_reflns_theta_max         25.05
_diffrn_reflns_theta_min         3.51
_exptl_absorpt_coefficient_mu    0.092
_exptl_absorpt_correction_T_max  0.9991
_exptl_absorpt_correction_T_min  0.9926
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS 2007/2 (Sheldrick, G.M., 2007)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.266
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             488
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.201
_refine_diff_density_min         -0.218
_refine_diff_density_rms         0.052
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     169
_refine_ls_number_reflns         1981
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0780
_refine_ls_R_factor_gt           0.0563
_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^)+(0.0291P)^2^+0.9131P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1149
_refine_ls_wR_factor_ref         0.1243
_reflns_number_gt                1603
_reflns_number_total             1981
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ce06659a.txt
_cod_data_source_block           Nbtl-III
_cod_original_sg_symbol_H-M      Pna21
_cod_database_code               7207654