Releasing a bound molecular spring with light: a visible light-triggered photosalient effect tied to polymorphism.
McGehee, Keegan; Saito, Koichiro; Kwaria, Dennis; Minamikawa, Hiroyuki; Norikane, Yasuo; Physical chemistry chemical physics : PCCP 26 (2024) 6834–6843; doi:10.1039/d3cp04691e

data_7248108
_publ_section_title
;
 Releasing a bound molecular spring with light: a visible light-triggered
 photosalient effect tied to polymorphism.
;
_journal_issue                   8
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              6834
_journal_page_last               6843
_journal_paper_doi               10.1039/d3cp04691e
_journal_volume                  26
_journal_year                    2024
_chemical_formula_sum            'C12 H6 Br4 N2'
_chemical_formula_weight         497.83
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_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2023-09-15 deposited with the CCDC.	2023-12-11 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 109.223(19)
_cell_angle_gamma                90
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_cell_length_c                   16.82(3)
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_cell_measurement_temperature    170(2)
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      3.30
_cell_volume                     1329(4)
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_diffrn_ambient_temperature      170(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Rigaku XtaLAB mini'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.1363
_diffrn_reflns_av_unetI/netI     0.1142
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.995
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -22
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_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.995
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.805
_diffrn_reflns_theta_min         3.331
_exptl_absorpt_coefficient_mu    12.091
_exptl_absorpt_correction_T_max  0.297
_exptl_absorpt_correction_T_min  0.222
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'REQAB (Rigaku, 1998)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    2.488
_exptl_crystal_description       prism
_exptl_crystal_F_000             928
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.100
_refine_diff_density_max         1.685
_refine_diff_density_min         -0.786
_refine_diff_density_rms         0.230
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     163
_refine_ls_number_reflns         3124
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.119
_refine_ls_R_factor_all          0.1802
_refine_ls_R_factor_gt           0.1144
_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^)+(0.0898P)^2^+21.0366P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2395
_refine_ls_wR_factor_ref         0.2757
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1837
_reflns_number_total             3124
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d3cp04691e4.cif
_cod_data_source_block           4BrAzo_cis
_cod_depositor_comments
'Adding full bibliography for 7248107--7248109.cif.'
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7248108
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.196
_shelx_estimated_absorpt_t_max   0.378
_shelx_res_checksum              26031