Rational molecular designs for drastic acceleration of the color-fading speed of photochromic naphthopyrans
Katsutoshi Arai; Yoichi Kobayashi; Jiro Abe; Chem.Commun. 51 (2015) 3057–; doi:10.1039/C4cc10294K

data_7116509
_publ_section_title
;
 Rational molecular designs for drastic acceleration of the color-fading
 speed of photochromic naphthopyrans
;
_journal_name_full               Chem.Commun.
_journal_page_first              3057
_journal_paper_doi               10.1039/C4cc10294K
_journal_volume                  51
_journal_year                    2015
_chemical_formula_sum            'C41 H26 O'
_chemical_formula_weight         534.62
_chemical_name_systematic        3,3diphenyl2(pyren1yl)3Hbenzo[f]chromene
_chemical_properties_physical    Photo-sensitive
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_audit_update_record
;
2014-10-28 deposited with the CCDC.
2015-01-15 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 98.5570(10)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   41.059(2)
_cell_length_b                   10.4431(6)
_cell_length_c                   13.0847(8)
_cell_measurement_temperature    90
_cell_volume                     5548.0(5)
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_diffrn_ambient_temperature      90
_diffrn_measured_fraction_theta_full 0.941
_diffrn_measured_fraction_theta_max 0.999
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0153
_diffrn_reflns_av_unetI/netI     0.0185
_diffrn_reflns_Laue_measured_fraction_full 0.941
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       48
_diffrn_reflns_limit_h_min       -42
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            12608
_diffrn_reflns_point_group_measured_fraction_full 0.941
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         24.708
_diffrn_reflns_theta_min         2.006
_exptl_absorpt_coefficient_mu    0.075
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.280
_exptl_crystal_description       block
_exptl_crystal_F_000             2240
_exptl_crystal_preparation       photochromic
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: methanol/ethyl acetate mixed solvent'
_exptl_crystal_size_max          0.600
_exptl_crystal_size_mid          0.500
_exptl_crystal_size_min          0.300
_refine_diff_density_max         0.194
_refine_diff_density_min         -0.183
_refine_diff_density_rms         0.035
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.954
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     379
_refine_ls_number_reflns         4734
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.954
_refine_ls_R_factor_all          0.0387
_refine_ls_R_factor_gt           0.0323
_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^)+(0.1000P)^2^+0.0978P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1084
_refine_ls_wR_factor_ref         0.1173
_reflns_Friedel_coverage         0.000
_reflns_number_gt                4098
_reflns_number_total             4734
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c4cc10294k2.cif
_cod_data_source_block           140324_2_0m
_cod_original_cell_volume        5548.0(6)
_cod_database_code               7116509
_shelx_estimated_absorpt_t_min   0.956
_shelx_estimated_absorpt_t_max   0.978
_shelxl_version_number           2013-3
_shelx_res_checksum              97617