C20H20O6
Ward, Robert S.; Light, Mark E.; Hursthouse, Michael B.; Crystal Structure Report Archive  (2000) 737–; doi:

data_1519260
_publ_section_title
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 C20H20O6
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_journal_name_full               'Crystal Structure Report Archive'
_journal_page_first              737
_journal_year                    2000
_chemical_formula_sum            'C20 H20 O6'
_chemical_formula_weight         356.36
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 94.2660(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.4814(3)
_cell_length_b                   7.2705(2)
_cell_length_c                   17.7911(4)
_cell_measurement_reflns_used    26399
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      30.51
_cell_measurement_theta_min      2.91
_cell_volume                     1738.99(7)
_computing_cell_refinement       'DENZO and COLLECT'
_computing_data_collection
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'DENZO (Otwinowski and Minor, 1997) & COLLECT (Hooft, 1998) '
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_computing_data_reduction        'DENZO and COLLECT'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Enraf Nonius KappaCCD area detector'
_diffrn_measurement_method       '\w and \f scans to fill Ewald sphere'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enraf Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0408
_diffrn_reflns_av_sigmaI/netI    0.0328
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            14074
_diffrn_reflns_theta_full        25.03
_diffrn_reflns_theta_max         25.03
_diffrn_reflns_theta_min         3.03
_exptl_absorpt_coefficient_mu    0.101
_exptl_absorpt_correction_T_max  0.9802
_exptl_absorpt_correction_T_min  0.9753
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SORTAV (R.H. Blessing, 1995, 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.361
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             752
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.209
_refine_diff_density_min         -0.190
_refine_diff_density_rms         0.038
_refine_ls_extinction_coef       0.0105(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     316
_refine_ls_number_reflns         3064
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0432
_refine_ls_R_factor_gt           0.0349
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0488P)^2^+0.4576P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0870
_refine_ls_wR_factor_ref         0.0919
_reflns_number_gt                2597
_reflns_number_total             3064
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            eCrystal-737.cif
_cod_data_source_block           s92
_cod_depositor_comments
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Citation :
Ward, Robert S. and Light, Mark E. and Hursthouse, Michael B. (2000) 
University of Southampton, Crystal Structure Report Archive. 

More at:
http://ecrystals.chem.soton.ac.uk/737/

The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Empirical' changed to
'empirical' according to the built-in table from CIF Core dictionary
named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 3105 2015-03-04 15:46:00Z robertas 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               1519260