Why do simple molecules with "isolated" phenyl rings emit visible light?
Zhang, Haoke; Zheng, Xiaoyan; Xie, Ni; He, Zikai; Liu, Junkai; Leung, Nelson L. C.; Niu, Yingli; Huang, Xuhui; Wong, Kam Sing; Kwok, Ryan T. K.; Sung, Herman H. Y.; Williams, Ian D.; Qin, Anjun; Lam, Jacky W. Y.; Tang, Ben Zhong; Journal of the American Chemical Society  (2017) –; doi:10.1021/jacs.7b08592

data_4126685
_publ_section_title
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 Why do simple molecules with &quot;isolated&quot; phenyl rings emit
 visible light?
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_journal_name_full               'Journal of the American Chemical Society'
_journal_paper_doi               10.1021/jacs.7b08592
_journal_year                    2017
_chemical_formula_sum            'C26 H22'
_chemical_formula_weight         334.44
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 91.238(8)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   17.6477(19)
_cell_length_b                   5.8820(7)
_cell_length_c                   17.6454(16)
_cell_measurement_reflns_used    3422
_cell_measurement_temperature    133(2)
_cell_measurement_theta_max      71.44
_cell_measurement_theta_min      2.50
_cell_volume                     1831.2(3)
_computing_cell_refinement
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_data_collection
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_data_reduction
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      133(2)
_diffrn_measured_fraction_theta_full 0.972
_diffrn_measured_fraction_theta_max 0.971
_diffrn_measurement_device_type  'Xcalibur, Sapphire3, Gemini ultra'
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_source         'Enhance Ultra (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0495
_diffrn_reflns_av_sigmaI/netI    0.0354
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            4812
_diffrn_reflns_theta_full        66.50
_diffrn_reflns_theta_max         67.47
_diffrn_reflns_theta_min         5.01
_exptl_absorpt_coefficient_mu    0.514
_exptl_absorpt_correction_T_max  1.00
_exptl_absorpt_correction_T_min  0.91
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.46 (release 27-08-2009 CrysAlis171 .NET)
(compiled Aug 27 2009,17:19:36)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.213
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             712
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.186
_refine_diff_density_min         -0.241
_refine_diff_density_rms         0.039
_refine_ls_extinction_coef       0.0029(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.015
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     128
_refine_ls_number_reflns         1594
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.015
_refine_ls_R_factor_all          0.0576
_refine_ls_R_factor_gt           0.0541
_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^)+(0.0850P)^2^+1.4000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1467
_refine_ls_wR_factor_ref         0.1506
_reflns_number_gt                1452
_reflns_number_total             1594
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja7b08592_si_002.cif
_cod_data_source_block           xie7cult
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 
;
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               4126685