Proton exchange and isomerisation reactions of photochromic and reverse photochromic spiro-pyrans and their merocyanine forms
Hobley, Jonathan; Malatesta, Vincenzo; Millini, Roberto; Montanari, Luciano; O Neil Parker, Jr, Wallace; Physical Chemistry Chemical Physics 1 (1999) 3259–; doi:10.1039/a902379h

data_7213065
_publ_section_title
;
 Proton exchange and isomerisation reactions of photochromic and reverse
 photochromic spiro-pyrans and their merocyanine forms
;
_journal_issue                   14
_journal_name_full               'Physical Chemistry Chemical Physics'
_journal_page_first              3259
_journal_paper_doi               10.1039/a902379h
_journal_volume                  1
_journal_year                    1999
_chemical_formula_sum            'C19 H17 N3 O5'
_chemical_formula_weight         367.36
_chemical_name_systematic
; 2,4-Cyclohexadiene-1-one-2,4-dinitro-6-[2-(1,3,3-trimethyl-2-

indolinidene)ethylidene]

;
_space_group_IT_number           2
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_atom_sites_solution_primary     direct
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_cell_angle_beta                 74.84(1)
_cell_angle_gamma                111.21(1)
_cell_formula_units_Z            2.00
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_cell_length_b                   9.449(1)
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_cell_measurement_temperature    298
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_cell_measurement_theta_min      11
_cell_measurement_wavelength     0.71069
_cell_volume                     851.1(2)
_diffrn_ambient_temperature      298
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_av_R_equivalents  0.00
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3756
_diffrn_reflns_theta_max         27
_diffrn_reflns_theta_min         3
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count 49
_diffrn_standards_number         1
_exptl_absorpt_coefficient_mu    0.1058
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            ' Dark red '
_exptl_crystal_density_diffrn    1.4334
_exptl_crystal_F_000             384.0
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.131
_refine_diff_density_min         -0.155
_refine_ls_goodness_of_fit_all   1.887
_refine_ls_goodness_of_fit_ref   1.231
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full-matrix
_refine_ls_number_parameters     244
_refine_ls_number_reflns         1625
_refine_ls_R_factor_gt           0.0518
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     'w = 1/\s^2^(F)'
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_reflns_number_gt                1635
_reflns_number_total             3756
_reflns_threshold_expression     F>3\s(F)
_cod_data_source_file            902379hsup1.cif
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_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value ' none ' changed to 'none'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value ' not measured ' was changed to
'?' - the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_atom_sites_solution_primary' value 'Direct Methods' was changed to
'direct'.

Automatic conversion script
Id: cif_fix_values 6452 2018-10-05 10:23:21Z andrius 
;
_cod_original_sg_symbol_H-M      ' P -1           '
_cod_original_formula_sum        'C19 H17 N3 O5 '
_cod_database_code               7213065