Para‒ferroelectric phase transition induces an excellent second harmonic generation response and a prominent switchable dielectric constant change based on a metal-free ionic crystal
Han, Ding-Chong; Li, Yu-Kong; Liu, Yao; Tan, Yu-Hui; Tang, Yun-Zhi; Wei, Wen-Juan; Du, Peng-Kang; Zhang, Hao; CrystEngComm 23 (2021) 5306–5313; doi:10.1039/D1CE00680K

data_7242951
_publ_section_title
;
 Para--ferroelectric phase transition induces an excellent second harmonic
 generation response and a prominent switchable dielectric constant change
 based on a metal-free ionic crystal
;
_journal_issue                   31
_journal_name_full               CrystEngComm
_journal_page_first              5306
_journal_page_last               5313
_journal_paper_doi               10.1039/D1CE00680K
_journal_volume                  23
_journal_year                    2021
_chemical_absolute_configuration unk
_chemical_formula_moiety         '2(Cl O4), C13 H16 N2'
_chemical_formula_sum            'C13 H16 Cl2 N2 O8'
_chemical_formula_weight         399.18
_space_group_crystal_system      orthorhombic
_space_group_IT_number           18
_space_group_name_Hall           'P 2 2ab'
_space_group_name_H-M_alt        'P 21 21 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_block_doi                 10.5517/ccdc.csd.cc27pr90
_audit_creation_date             2021-05-30
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_audit_update_record
;
2021-05-31 deposited with the CCDC.	2021-06-01 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   13.0155(7)
_cell_length_b                   13.2744(7)
_cell_length_c                   4.9013(2)
_cell_measurement_reflns_used    1486
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.140
_cell_measurement_theta_min      3.076
_cell_volume                     846.81(7)
_computing_cell_refinement       'SAINT V8.38A (?, 2016)'
_computing_data_reduction        'SAINT V8.38A (?, 2016)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0141
_diffrn_reflns_av_unetI/netI     0.0144
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            4419
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.19
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.429
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6337
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.0499 before and 0.0417 after correction.
The Ratio of minimum to maximum transmission is 0.8499.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear whiteish white'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   whiteish
_exptl_crystal_colour_primary    white
_exptl_crystal_density_diffrn    1.566
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             412
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.673
_refine_diff_density_min         -0.618
_refine_diff_density_rms         0.075
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.182
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     115
_refine_ls_number_reflns         1483
_refine_ls_number_restraints     35
_refine_ls_restrained_S_all      1.304
_refine_ls_R_factor_all          0.0766
_refine_ls_R_factor_gt           0.0657
_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^)+(0.1080P)^2^+0.6241P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1970
_refine_ls_wR_factor_ref         0.2120
_reflns_number_gt                1224
_reflns_number_total             1483
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            d1ce00680k2.cif
_cod_data_source_block           qww
_cod_depositor_comments          'Adding full bibliography for 7242951.cif.'
_cod_database_code               7242951
_olex2_refinement_description
;
1. Twinned data refinement
 Scales: 0.8(3)
 0.2(3)
2. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
3. Rigid bond restraints
 N1, C4, C5, C6
 with sigma for 1-2 distances of 0.002 and sigma for 1-3 distances of 0.002
4. Uiso/Uaniso restraints and constraints
Uanis(N1) \\sim Ueq, Uanis(C4) \\sim Ueq, Uanis(C5) \\sim Ueq, Uanis(C6) \\sim
Ueq, Uanis(C7) \\sim Ueq: with sigma of 0.002 and sigma for terminal atoms of
0.004
5. Others
 Fixed Sof: H1A(0.5) H1B(0.5)
6.a Secondary CH2 refined with riding coordinates:
 C1(H1A,H1B), C2(H2A,H2B)
6.b Aromatic/amide H refined with riding coordinates:
 N1(H1), C4(H4), C5(H5), C6(H6), C7(H7)
;
_olex2_submission_special_instructions 'No special instructions were received'