Point-to-Volume Engineering Enables Enhanced Birefringence and Wide Bandgap in Hybrid Halide Ultraviolet Nonlinear Optical Crystals
Wu, Jiajing; Li, Ruo-Nan; Yao, Wen-Dong; Fu, Yi-Fan; Guo, Sheng-Ping; Chemical Science  (2026) –; doi:10.1039/D6SC00466K

data_1577110
_publ_section_title
;
 Point-to-Volume Engineering Enables Enhanced Birefringence and Wide
 Bandgap in Hybrid Halide Ultraviolet Nonlinear Optical Crystals
;
_journal_name_full               'Chemical Science'
_journal_paper_doi               10.1039/D6SC00466K
_journal_year                    2026
_chemical_formula_moiety         '2(Cl), C4 H13 N5'
_chemical_formula_sum            'C4 H13 Cl2 N5'
_chemical_formula_weight         202.09
_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'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     iterative
_audit_creation_date             2026-01-11
_audit_creation_method
;
Olex2 1.5
(compiled 2021.12.09 svn.r5202d8cf for OlexSys, GUI svn.r6498)
;
_audit_update_record
;
2026-01-11 deposited with the CCDC.	2026-04-16 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 105.077(2)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   7.1245(5)
_cell_length_b                   5.7932(4)
_cell_length_c                   12.5446(8)
_cell_measurement_reflns_used    4093
_cell_measurement_temperature    296.15
_cell_measurement_theta_max      26.95
_cell_measurement_theta_min      2.96
_cell_volume                     499.94(6)
_computing_cell_refinement       'SAINT v8.37A (Bruker, 2015)'
_computing_data_reduction        'SAINT v8.37A (Bruker, 2015)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'olex2.solve 1.5 (Bourhis et al., 2015)'
_diffrn_ambient_temperature      296.15
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0305
_diffrn_reflns_av_unetI/netI     0.0381
_diffrn_reflns_Laue_measured_fraction_full 0.990
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            7342
_diffrn_reflns_point_group_measured_fraction_full 0.987
_diffrn_reflns_point_group_measured_fraction_max 0.990
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.465
_diffrn_reflns_theta_min         2.961
_diffrn_source_current           1.0
_diffrn_source_power             0.05
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.603
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6591
_exptl_absorpt_correction_type   none
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1063 before and 0.0475 after correction.
The Ratio of minimum to maximum transmission is 0.8840.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear light colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.343
_exptl_crystal_description       block
_exptl_crystal_F_000             212
_refine_diff_density_max         0.236
_refine_diff_density_min         -0.179
_refine_diff_density_rms         0.043
_refine_ls_abs_structure_details
;
 Flack x determined using 762 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.04(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     102
_refine_ls_number_reflns         2262
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0439
_refine_ls_R_factor_gt           0.0330
_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^)+(0.0352P)^2^+0.0348P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0680
_refine_ls_wR_factor_ref         0.0714
_reflns_Friedel_coverage         0.812
_reflns_Friedel_fraction_full    0.984
_reflns_Friedel_fraction_max     0.987
_reflns_number_gt                1958
_reflns_number_total             2262
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6sc00466k2.cif
_cod_data_source_block           cl
_cod_database_code               1577110
_shelx_shelxl_version_number     2018/3
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All N(H) groups, All N(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Aromatic/amide H refined with riding coordinates:
 N3(H3)
2.b X=CH2 refined with riding coordinates:
 N2(H2A,H2B), N4(H4A,H4B), N1(H1A,H1B)
2.c Idealised Me refined as rotating group:
 C3(H3A,H3B,H3C), C4(H4C,H4D,H4E)
;
_shelx_res_checksum              29321
_olex2_submission_special_instructions 'No special instructions were received'