Diversity in a simple co-crystal: racemic and kryptoracemic behaviour
U. B. Rao Khandavilli; Matteo Lusi; Balakrishna R. Bhogala; Anita R. Maguire; Matthias Stein; Simon E. Lawrence; Chem.Commun. 52 (2016) 8309–8312; doi:10.1039/C6CC04148E

data_7119651
_publ_section_title
;
 Diversity in a simple co-crystal: racemic and kryptoracemic behaviour
;
_journal_name_full               Chem.Commun.
_journal_page_first              8309
_journal_page_last               8312
_journal_paper_doi               10.1039/C6CC04148E
_journal_volume                  52
_journal_year                    2016
_chemical_absolute_configuration unk
_chemical_formula_sum            'C18 H21 N O4'
_chemical_formula_weight         315.36
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014
_audit_update_record
;
2016-05-16 deposited with the CCDC.
2016-06-08 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 93.913(11)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   9.882(4)
_cell_length_b                   20.953(8)
_cell_length_c                   16.215(6)
_cell_measurement_reflns_used    3281
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      20
_cell_measurement_theta_min      3
_cell_volume                     3350(2)
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2014)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.871
_diffrn_measured_fraction_theta_max 0.843
_diffrn_measurement_device_type  'Bruker D8 Quest'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0916
_diffrn_reflns_av_unetI/netI     0.1597
_diffrn_reflns_Laue_measured_fraction_max 0.843
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       27
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            21286
_diffrn_reflns_point_group_measured_fraction_max 0.644
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.699
_diffrn_reflns_theta_min         2.675
_exptl_absorpt_coefficient_mu    0.088
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.4205
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.251
_exptl_crystal_description       needle
_exptl_crystal_F_000             1344
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.440
_refine_diff_density_min         -0.499
_refine_diff_density_rms         0.105
_refine_ls_abs_structure_details
;
 Flack x determined using 1578 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.7(10)
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     845
_refine_ls_number_reflns         10125
_refine_ls_number_restraints     19
_refine_ls_restrained_S_all      1.027
_refine_ls_R_factor_all          0.1735
_refine_ls_R_factor_gt           0.1089
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1409P)^2^+8.3710P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2653
_refine_ls_wR_factor_ref         0.3014
_reflns_Friedel_coverage         0.488
_reflns_Friedel_fraction_full    0.498
_reflns_Friedel_fraction_max     0.435
_reflns_number_gt                6088
_reflns_number_total             10125
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c6cc04148e2.cif
_cod_data_source_block           Form_II
_cod_database_code               7119651
_shelxl_version_number           2014-3
_shelx_res_checksum              11025
_shelx_hkl_checksum              82608