A combined crystallographic and theoretical study of weak intermolecular interactions in crystalline squaric acid esters and amides
Prohens, Rafel; Frontera, Antonio; Portell, Anna; Font-Bardia, Merce; Bauza, Antonio; CrystEngComm  (2017) –; doi:10.1039/C7CE00556C

data_7228240
_publ_section_title
;
 A combined crystallographic and theoretical study of weak intermolecular
 interactions in crystalline squaric acid esters and amides
;
_journal_name_full               CrystEngComm
_journal_paper_doi               10.1039/C7CE00556C
_journal_year                    2017
_chemical_formula_moiety         'C13 H14 N2 O3'
_chemical_formula_sum            'C13 H14 N2 O3'
_chemical_formula_weight         246.26
_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           SHELXL-97
_audit_update_record
;
2017-03-21 deposited with the CCDC.
2017-05-08 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 92.07(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.435(5)
_cell_length_b                   14.028(7)
_cell_length_c                   12.008(6)
_cell_measurement_reflns_used    216
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      31
_cell_measurement_theta_min      3
_cell_volume                     1251.6(12)
_computing_cell_refinement       AUTOMAR
_computing_data_collection       MARXDS
_computing_data_reduction        MARSCALE
_computing_molecular_graphics    'ORTEP (Brueggermann and Smith, 1990)'
_computing_publication_material  'PLATON (Spek, 1990)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.944
_diffrn_measured_fraction_theta_max 0.812
_diffrn_measurement_device_type  'MAR345 with image plate detector'
_diffrn_measurement_method       'phi scan'
_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  0.0380
_diffrn_reflns_av_sigmaI/netI    0.0224
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            11149
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         30.33
_diffrn_reflns_theta_min         2.90
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.307
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             520
_exptl_crystal_size_max          0.09
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.200
_refine_diff_density_min         -0.305
_refine_diff_density_rms         0.068
_refine_ls_extinction_coef       0.045(5)
_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   1.160
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     164
_refine_ls_number_reflns         3058
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      1.171
_refine_ls_R_factor_all          0.0536
_refine_ls_R_factor_gt           0.0475
_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^)+(0.0544P)^2^+0.1199P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1278
_refine_ls_wR_factor_ref         0.1312
_reflns_number_gt                2598
_reflns_number_total             3058
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c7ce00556c2.cif
_cod_data_source_block           annm61b
_cod_original_sg_symbol_H-M      P21/n
_cod_database_code               7228240