Unprecedented ππ interaction between an aromatic ring and a pseudo-aromatic ring formed through intramolecular H-bonding in a bidentate Schiff base ligand: crystal structure and DFT calculations.
Dutta, Arpan; Jana, Atish Dipankar; Gangopadhyay, Sumana; Das, Kalyan Kumar; Marek, Jaromir; Marek, Radek; Brus, Jiri; Ali, Mahammad; Physical chemistry chemical physics : PCCP 13 (2011) 15845–15853; doi:10.1039/c1cp21047e

data_7206437
_publ_section_title
;
 Unprecedented \p\p interaction between an aromatic ring and a
 pseudo-aromatic ring formed through intramolecular H-bonding in a
 bidentate Schiff base ligand: crystal structure and DFT calculations.
;
_journal_issue                   35
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              15845
_journal_page_last               15853
_journal_paper_doi               10.1039/c1cp21047e
_journal_volume                  13
_journal_year                    2011
_chemical_formula_sum            'C15 H15 N2.5 O0.5'
_chemical_formula_weight         238.29
_chemical_name_systematic
;
?
;
_space_group_IT_number           14
_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                 106.713(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.3306(2)
_cell_length_b                   20.0666(7)
_cell_length_c                   9.8174(2)
_cell_measurement_temperature    120(2)
_cell_volume                     1194.46(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_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  0.0522
_diffrn_reflns_av_sigmaI/netI    0.0303
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            6830
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.97
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  0.9796
_exptl_absorpt_correction_T_min  0.9598
_exptl_crystal_density_diffrn    1.325
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             506
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.336
_refine_diff_density_min         -0.249
_refine_diff_density_rms         0.059
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.069
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     172
_refine_ls_number_reflns         2090
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.069
_refine_ls_R_factor_all          0.0413
_refine_ls_R_factor_gt           0.0329
_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^+0.5000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0936
_refine_ls_wR_factor_ref         0.1184
_reflns_number_gt                1758
_reflns_number_total             2090
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cp21047e.txt
_cod_data_source_block           in10
_cod_original_cell_volume        1194.46(6)
_cod_original_formula_sum        'C15 H15 N2.50 O0.50'
_cod_database_code               7206437