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_7248107
_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
_space_group_crystal_system      monoclinic
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_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/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                 112.61(3)
_cell_angle_gamma                90
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_cell_length_c                   8.31(2)
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_cell_measurement_temperature    170(2)
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      3.40
_cell_volume                     1457(6)
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_diffrn_ambient_temperature      170(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Rigaku XtaLAB mini'
_diffrn_measurement_method       \w
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0790
_diffrn_reflns_av_unetI/netI     0.0608
_diffrn_reflns_Laue_measured_fraction_full 0.995
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       15
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_diffrn_reflns_limit_l_max       10
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_diffrn_reflns_number            6993
_diffrn_reflns_point_group_measured_fraction_full 0.995
_diffrn_reflns_point_group_measured_fraction_max 0.992
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.499
_diffrn_reflns_theta_min         3.356
_exptl_absorpt_coefficient_mu    11.035
_exptl_absorpt_correction_T_max  0.331
_exptl_absorpt_correction_T_min  0.190
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'REQAB (Rigaku, 1998)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    2.270
_exptl_crystal_description       needle
_exptl_crystal_F_000             928
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.300
_exptl_crystal_size_min          0.100
_refine_diff_density_max         1.201
_refine_diff_density_min         -1.239
_refine_diff_density_rms         0.215
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         1658
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.069
_refine_ls_R_factor_all          0.0820
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_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1000P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1711
_refine_ls_wR_factor_ref         0.1846
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1141
_reflns_number_total             1658
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d3cp04691e4.cif
_cod_data_source_block           4BrAzo_trans_alpha
_cod_depositor_comments
'Adding full bibliography for 7248107--7248109.cif.'
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               7248107
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.073
_shelx_estimated_absorpt_t_max   0.405
_shelx_res_checksum              9259