9-Methyl-8,11,12-trioxatricyclo[7.2.1.0^2,7^]dodeca-2,4,6-trien-10-one
Eilers, Frank; Bach, Thorsten; Fröhlich, Roland; Acta Crystallographica Section C 54 (1998) 1011–1013; doi:10.1107/S0108270198001528

data_2007443
_publ_section_title
;
 9-Methyl-8,11,12-trioxatricyclo[7.2.1.0^2,7^]dodeca-2,4,6-trien-10-one
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1011
_journal_page_last               1013
_journal_paper_doi               10.1107/S0108270198001528
_journal_volume                  54
_journal_year                    1998
_chemical_formula_moiety         'C10 H8 O4'
_chemical_formula_sum            'C10 H8 O4'
_chemical_formula_weight         192.16
_chemical_name_systematic
;
9-Methyl-8,11,12-trioxatricyclo[7.2.1.0^2,7^]dodeca-2,4,6-trien-10-one
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.8380(10)
_cell_length_b                   7.2310(10)
_cell_length_c                   20.5480(10)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      46.44
_cell_measurement_theta_min      40.34
_cell_volume                     867.4(2)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection       'CAD-4 EXPRESS (Enraf-Nonius, 1994)'
_computing_data_reduction        'MolEN (Fair, 1990)'
_computing_molecular_graphics    'DIAMOND (Brandenburg, 1996)'
_computing_publication_material  SHELXL93
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      223(2)
_diffrn_measurement_device       'Enraf Nonius CAD4'
_diffrn_measurement_method       '\w/2\q scans'
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0104
_diffrn_reflns_limit_h_max       0
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       0
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       0
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            1068
_diffrn_reflns_theta_max         74.26
_diffrn_reflns_theta_min         4.30
_diffrn_standards_decay_%        2.7
_diffrn_standards_interval_count 250
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.978
_exptl_absorpt_correction_T_max  0.999
_exptl_absorpt_correction_T_min  0.941
_exptl_absorpt_correction_type   'empirical via \y scan data (Fair, 1990)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.471
_exptl_crystal_density_meas      ?
_exptl_crystal_description       plate
_exptl_crystal_F_000             400
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.50
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.192
_refine_diff_density_min         -0.139
_refine_ls_abs_structure_details 'Flack (1983)'
_refine_ls_abs_structure_Flack   -0.2(4)
_refine_ls_extinction_coef       0.0160(14)
_refine_ls_extinction_method     SHELXL93
_refine_ls_goodness_of_fit_all   1.132
_refine_ls_goodness_of_fit_obs   1.139
_refine_ls_hydrogen_treatment
;
H atoms calculated and refined as riding atoms with U = 1.2(1.5) \\times
U~host~
;
_refine_ls_matrix_type           full
_refine_ls_number_parameters     129
_refine_ls_number_reflns         1068
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.132
_refine_ls_restrained_S_obs      1.139
_refine_ls_R_factor_all          0.031
_refine_ls_R_factor_obs          .031
_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^)+(0.0461P)^2^+0.1854P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.090
_refine_ls_wR_factor_obs         .090
_reflns_number_observed          1051
_reflns_number_total             1068
_reflns_observed_criterion       I>2sigma(I)
_cod_data_source_file            jz1270.cif
_cod_data_source_block           I
_cod_depositor_comments
;
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:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0461P)^2^+0.1854P] 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^)+(0.0461P)^2^+0.1854P] 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               2007443