Direct Observation of the Symmetrical and Asymmetrical Protonation States in Molecular Crystals.
Ma, Suqian; Zhang, Jibo; Liu, Yingjie; Qian, Jingyu; Xu, Bin; Tian, Wenjing; The journal of physical chemistry letters 8 (2017) 3068–3072; doi:10.1021/acs.jpclett.7b01454

data_8000250
_publ_section_title
;
 Direct Observation of the Symmetrical and Asymmetrical Protonation States
 in Molecular Crystals.
;
_journal_issue                   13
_journal_name_full               'The journal of physical chemistry letters'
_journal_page_first              3068
_journal_page_last               3072
_journal_paper_doi               10.1021/acs.jpclett.7b01454
_journal_volume                  8
_journal_year                    2017
_chemical_formula_sum            'C28 H20 N2'
_chemical_formula_weight         384.46
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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                 95.95(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   7.5957(15)
_cell_length_b                   5.7108(11)
_cell_length_c                   22.899(5)
_cell_measurement_reflns_used    9226
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      3.08
_cell_volume                     988.0(4)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  ccd
_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  0.0213
_diffrn_reflns_av_sigmaI/netI    0.0182
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       29
_diffrn_reflns_limit_l_min       -29
_diffrn_reflns_number            9226
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         3.08
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  0.9940
_exptl_absorpt_correction_T_min  0.9910
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'not given'
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    1.292
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       palte
_exptl_crystal_F_000             404
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.227
_refine_diff_density_min         -0.158
_refine_diff_density_rms         0.033
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     136
_refine_ls_number_reflns         2253
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.081
_refine_ls_R_factor_all          0.0596
_refine_ls_R_factor_gt           0.0428
_refine_ls_shift/su_max          0.019
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0720P)^2^+0.1187P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1269
_refine_ls_wR_factor_ref         0.1380
_reflns_number_gt                1634
_reflns_number_total             2253
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jz7b01454_si_002.cif
_cod_data_source_block           BP4VA
_cod_original_cell_volume        987.9(3)
_cod_original_sg_symbol_H-M      P_21/c
_cod_database_code               8000250