Mechanochromism triggered fluorescent color switching among polymorphs of a natural fluorescence pigment.
Li, Meiqi; Zhang, Qi; Wang, Jian-Rong; Mei, Xuefeng; Chemical communications (Cambridge, England) 52 (2016) 11288–11291; doi:10.1039/c6cc04958c

data_7124842
_publ_section_title
;
 Mechanochromism triggered fluorescent color switching among polymorphs of
 a natural fluorescence pigment.
;
_journal_issue                   75
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              11288
_journal_page_last               11291
_journal_paper_doi               10.1039/c6cc04958c
_journal_volume                  52
_journal_year                    2016
_chemical_formula_moiety         'C15 H10 O5'
_chemical_formula_sum            'C15 H10 O5'
_chemical_formula_weight         270.23
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_date             2016-08-15
_audit_creation_method
;
Olex2 1.2-beta
(compiled 2016.07.26 svn.r3321 for OlexSys, GUI svn.r5206)
;
_audit_update_record
;
2016-08-15 deposited with the CCDC.
2016-08-22 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 95.544(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   16.6384(6)
_cell_length_b                   3.6887(2)
_cell_length_c                   19.4060(7)
_cell_measurement_reflns_used    2177
_cell_measurement_temperature    100
_cell_measurement_theta_max      24.37
_cell_measurement_theta_min      2.46
_cell_volume                     1185.45(9)
_computing_cell_refinement       'SAINT v7.68A (Bruker, 2009)'
_computing_data_collection       'SMART (Bruker, 2009)'
_computing_data_reduction        'SAINT v7.68A (Bruker, 2009)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_diffrn_ambient_temperature      100.0
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0415
_diffrn_reflns_av_unetI/netI     0.0307
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       -4
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            12962
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        24.397
_diffrn_reflns_theta_max         24.397
_diffrn_reflns_theta_min         1.540
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.115
_exptl_absorpt_correction_T_max  0.7451
_exptl_absorpt_correction_T_min  0.6501
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0896 before and 0.0532 after correction.
The Ratio of minimum to maximum transmission is 0.8725.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            orange
_exptl_crystal_colour_primary    orange
_exptl_crystal_density_diffrn    1.514
_exptl_crystal_description       needle
_exptl_crystal_F_000             560
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.429
_refine_diff_density_min         -0.389
_refine_diff_density_rms         0.063
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     186
_refine_ls_number_reflns         1949
_refine_ls_number_restraints     45
_refine_ls_restrained_S_all      1.072
_refine_ls_R_factor_all          0.1011
_refine_ls_R_factor_gt           0.0682
_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^)+(0.1005P)^2^+2.0877P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1839
_refine_ls_wR_factor_ref         0.2158
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1317
_reflns_number_total             1949
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c6cc04958c2.cif
_cod_data_source_block           mo_2015505_0m_sq_s
_cod_database_code               7124842
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, H4 of O4
 At 1.5 times of:
  All C(H,H,H) groups, H3 of O3, H5 of O5
2. Rigid bond restraints
 O4, C9
 with sigma for 1-2 distances of 0.002 and sigma for 1-3 distances of 0.002
 C13, C14
 with sigma for 1-2 distances of 0.002 and sigma for 1-3 distances of 0.002
 C2, C7
 with sigma for 1-2 distances of 0.005 and sigma for 1-3 distances of 0.005
3. Uiso/Uaniso restraints and constraints
C2 \\sim C7: within 2A with sigma of 0.002 and sigma for terminal atoms of 0.004
Uanis(O4) \\sim Ueq, Uanis(C9) \\sim Ueq, Uanis(C2) \\sim Ueq, Uanis(C7) \\sim
Ueq, Uanis(C13) \\sim Ueq, Uanis(C12) \\sim Ueq: with sigma of 0.005 and sigma
for terminal atoms of 0.01
4.a Aromatic/amide H refined with riding coordinates:
 C8(H8), C10(H10), C14(H14), C12(H12)
4.b Tetrahedral OH refined with riding coordinates:
 O4(H4)
4.c Idealised Me refined as rotating group:
 C15(H15A,H15B,H15C)
4.d Idealised tetrahedral OH refined as rotating group:
 O3(H3)
;
_shelx_fab_checksum              70907
_shelx_shelxl_version_number     2014/7
_olex2_submission_special_instructions 'No special instructions were received'