4,4,4',4',7,7'-Hexamethyl-2,2'-spirobichroman
Ejsmont, Krzysztof; Kyzioł, Janusz; Nowakowska, Ewa; Zaleski, Jacek; Acta Crystallographica Section C 56 (2000) 93–94; doi:10.1107/S0108270199013190

data_2010531
_publ_section_title
;
 4,4,4',4',7,7'-Hexamethyl-2,2'-spirobichroman
;
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              93
_journal_page_last               94
_journal_paper_doi               10.1107/S0108270199013190
_journal_volume                  56
_journal_year                    2000
_chemical_formula_sum            'C23 H28 O2'
_chemical_formula_weight         336.45
_space_group_IT_number           56
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ab 2ac'
_symmetry_space_group_name_H-M   'P c c n'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.613(3)
_cell_length_b                   10.557(2)
_cell_length_c                   11.259(2)
_cell_measurement_reflns_used    21
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      20
_cell_measurement_theta_min      10
_cell_volume                     1974.6(6)
_computing_cell_refinement       'Kuma Diffraction Software'
_computing_data_collection       'Kuma Diffraction Software (Kuma, 1998)'
_computing_data_reduction        'Kuma Diffraction Software'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 1990)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997b)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full .788
_diffrn_measured_fraction_theta_max .788
_diffrn_measurement_device_type  'Kuma KM-4'
_diffrn_measurement_method       \w-\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .021
_diffrn_reflns_av_sigmaI/netI    .0157
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            9984
_diffrn_reflns_theta_full        25.06
_diffrn_reflns_theta_max         25.06
_diffrn_reflns_theta_min         2.92
_diffrn_standards_decay_%        1.7
_diffrn_standards_interval_count 50
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    .070
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.132
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             716
_exptl_crystal_size_max          .7
_exptl_crystal_size_mid          .4
_exptl_crystal_size_min          .3
_refine_diff_density_max         .162
_refine_diff_density_min         -.118
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.156
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     170
_refine_ls_number_reflns         1592
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.156
_refine_ls_R_factor_all          .075
_refine_ls_R_factor_gt           .046
_refine_ls_shift/su_max          .001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0546P)^2^+0.4667P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .131
_reflns_number_gt                1175
_reflns_number_total             1592
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gd1069.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value '?'' 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:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0546P)^2^+0.4667P] 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^)+(0.0546P)^2^+0.4667P] where P = (Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               2010531
_cod_database_fobs_code          2010531