Photochromic Properties of Spiro[fluorene-chromenes]
Aldoshin, Sergei; Chuev, Igor; Filipenko, Olga; Pozzo, Jean Luc; Lokshin, Vladimir; Pèpe, Gérard; Acta Crystallographica Section C 54 (1998) 1720–1722; doi:10.1107/S0108270198004727

data_2007784
_publ_section_title
;
 Photochromic Properties of Spiro[fluorene-chromenes]
;
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1720
_journal_page_last               1722
_journal_paper_doi               10.1107/S0108270198004727
_journal_volume                  54
_journal_year                    1998
_chemical_formula_analytical     'C25 H16 O'
_chemical_formula_moiety         'C25 H16 O'
_chemical_formula_structural     'C25 H16 O'
_chemical_formula_sum            'C25 H16 O'
_chemical_formula_weight         332.38
_chemical_melting_point          410.15
_chemical_name_common            spiro[fluorene-chromenes]
_chemical_name_systematic
;
spiro[fluorene-9,2'-[2H]naphto[1,2-b]pyrane
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_cell_angle_alpha                90.00
_cell_angle_beta                 112.81(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.768(3)
_cell_length_b                   7.0570(10)
_cell_length_c                   17.999(4)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      20.
_cell_measurement_theta_min      10.
_cell_volume                     1729.1(7)
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL93
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'KM-4 diffractometer'
_diffrn_measurement_method       \q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0197
_diffrn_reflns_av_sigmaI/netI    0.0245
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3618
_diffrn_reflns_theta_max         80.29
_diffrn_reflns_theta_min         3.31
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.593
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.277
_exptl_crystal_density_method    none
_exptl_crystal_description       needle
_exptl_crystal_F_000             696
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.160
_refine_diff_density_min         -0.209
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.180
_refine_ls_goodness_of_fit_obs   1.122
_refine_ls_hydrogen_treatment
;
All H-atom parameters refined
;
_refine_ls_matrix_type           full
_refine_ls_number_parameters     299
_refine_ls_number_reflns         3520
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.180
_refine_ls_restrained_S_obs      1.122
_refine_ls_R_factor_all          0.0789
_refine_ls_R_factor_obs          0.0383
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0460P)^2^+0.5461P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1438
_refine_ls_wR_factor_obs         0.1049
_reflns_number_observed          2189
_reflns_number_total             3520
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            bm1220.cif
_cod_data_source_block           IV
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_geom_bond_publ_flag' value 'Y' changed to 'y' according to
'/home/saulius/struct/CIF-dictionaries/cif_core.dic' dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29 (8 times).

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '137\%' was changed to '410.15' - it
was converted from degrees Celsius(C) to Kelvins(K).

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_chemical_melting_point' value '137\%' was changed to '410.15' - it
was converted from degrees Celsius(C) to
Kelvins(K).

'_symmetry_cell_setting' value 'Monoclinic' changed to
'monoclinic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

'_geom_bond_publ_flag'
value 'Y' changed to 'y' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29 (8
times).

'_geom_angle_publ_flag' value 'Y' changed to 'y' according
to /home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary
named 'cif_core.dic' version 2.4.1 from 2010-06-29 (11
times).

'_geom_torsion_publ_flag' value 'Y' changed to 'y' according
to /home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary
named 'cif_core.dic' version 2.4.1 from 2010-06-29 (7 times).

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0460P)^2^+0.5461P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
1/[\s^2^(Fo^2^)+(0.0460P)^2^+0.5461P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1729.1(6)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2007784