A novel chiral <i>C</i>~2~ axially symmetric acenaphthoquinone diketal
Parvez, Masood; Simion, Dan V.; Sorensen, Ted S.; Acta Crystallographica Section E 57 (2001) o366–o367; doi:10.1107/S1600536801005049

data_2200165
_publ_section_title
;
 A novel chiral <i>C</i>~2~ axially symmetric acenaphthoquinone diketal
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o366
_journal_page_last               o367
_journal_paper_doi               10.1107/S1600536801005049
_journal_volume                  57
_journal_year                    2001
_chemical_formula_iupac          'C20 H22 O4'
_chemical_formula_moiety         'C20 H22 O4'
_chemical_formula_sum            'C20 H22 O4'
_chemical_formula_weight         326.38
_chemical_name_common            'bis Dioxane'
_chemical_name_systematic
;
(-)-(4R,5R,4''R,5''R)-4,5,4'',5''-Tetramethyldispiro[1,3-dioxalane-
2,1'(2'H)-acenaphthylene-2',2''-1,3-dioxalane]
;
_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'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.799(3)
_cell_length_b                   19.331(5)
_cell_length_c                   9.054(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      15.0
_cell_measurement_theta_min      10.0
_cell_volume                     1715.0(9)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;MSC/AFC Diffractometer Control Software (Molecular Structure Corporation,
 1988)
;
_computing_data_reduction
'TEXSAN (Molecular Structure Corporation, 1994)'
_computing_molecular_graphics    TEXSAN
_computing_publication_material  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXS97 (Sheldrick, 1997)'
_computing_structure_solution    'SAPI91 (Fan, 1991)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 1.00
_diffrn_measured_fraction_theta_max 1.00
_diffrn_measurement_device_type  'Rigaku AFC-6S'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71069
_diffrn_reflns_av_R_equivalents  .00
_diffrn_reflns_av_sigmaI/netI    .12
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1758
_diffrn_reflns_theta_full        25.0
_diffrn_reflns_theta_max         25.0
_diffrn_reflns_theta_min         2.0
_diffrn_standards_decay_%        <0.5
_diffrn_standards_interval_count 200
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    .09
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.264
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             696
_exptl_crystal_size_max          .50
_exptl_crystal_size_mid          .21
_exptl_crystal_size_min          .13
_refine_diff_density_max         .22
_refine_diff_density_min         -.24
_refine_ls_abs_structure_details '(Flack, 1983)'
_refine_ls_abs_structure_Flack   -1(4)
_refine_ls_extinction_coef       .013(3)
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.00
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         1758
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.00
_refine_ls_R_factor_all          .154
_refine_ls_R_factor_gt           .040
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         .00
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0835P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .167
_reflns_number_gt                831
_reflns_number_total             1758
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            cv6011.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 
;
_cod_database_code               2200165
_cod_database_fobs_code          2200165