Lignin Model Compounds: 4,4'-<i>O</i>-Dimethyldehydrodiacetovanillone and 4,4'-<i>O</i>-Diethyldehydrodiacetovanillone
Ferreira, Márcia A.; Costa, Márcia D. D.; Mendes, Isolda M. C.; Drumond, Mariza G.; Piló-Veloso, Dorila; Fernandes, Nelson G.; Acta Crystallographica Section C 54 (1998) 837–840; doi:10.1107/S0108270197018015

data_2007312
_publ_section_title
;
 Lignin Model Compounds: 4,4'-<i>O</i>-Dimethyldehydrodiacetovanillone
 and 4,4'-<i>O</i>-Diethyldehydrodiacetovanillone
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              837
_journal_page_last               840
_journal_paper_doi               10.1107/S0108270197018015
_journal_volume                  54
_journal_year                    1998
_chemical_formula_sum            'C20 H22 O6'
_chemical_formula_weight         358.38
_chemical_name_systematic
;
5,5'-diacetyl-2,2',3,3'-tetramethoxy-1,1'-biphenyl
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_cell_angle_alpha                90.0
_cell_angle_beta                 124.513(4)
_cell_angle_gamma                90.0
_cell_formula_units_Z            4
_cell_length_a                   20.090(2)
_cell_length_b                   7.0879(6)
_cell_length_c                   15.4140(10)
_cell_measurement_reflns_used    27
_cell_measurement_temperature    298
_cell_measurement_theta_max      12.0
_cell_measurement_theta_min      5.0
_cell_volume                     1808.6(3)
_computing_cell_refinement       XSCANS
_computing_data_collection       'XSCANS, (Siemens, 1991)'
_computing_data_reduction        XSCANS
_computing_molecular_graphics    'XP (SHELXTL-PC)'
_computing_publication_material  'XPUBL (SHELXTL-PC)'
_computing_structure_refinement  'DUPALS (Lundgren, 1982)'
_computing_structure_solution    'XS (SHELXTL-PC; Sheldrick, 1990)'
_diffrn_ambient_temperature      298
_diffrn_measurement_device       'Siemens P4 diffractometer'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         xray_tube
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0191
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -1
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            3337
_diffrn_reflns_theta_max         30.00
_diffrn_reflns_theta_min         2.46
_diffrn_standards_decay_%        'less than 1'
_diffrn_standards_interval_count 297
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.10
_exptl_absorpt_correction_T_max  .9862
_exptl_absorpt_correction_T_min  .9599
_exptl_absorpt_correction_type   'Analytical (Lundgren, 1982)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.316
_exptl_crystal_density_method    none
_exptl_crystal_description       prism
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.10
_refine_diff_density_max         .183
_refine_diff_density_min         -.140
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.8505
_refine_ls_goodness_of_fit_obs   1.8505
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_constraints    9
_refine_ls_number_parameters     153
_refine_ls_number_reflns         2652
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          .0602
_refine_ls_R_factor_obs          .0602
_refine_ls_shift/esd_max         .01538
_refine_ls_shift/esd_mean        .00075
_refine_ls_structure_factor_coef F^2^
_refine_ls_weighting_details     'w = 1/\s^2^(F)^2^'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         .0886
_refine_ls_wR_factor_obs         .0886
_reflns_number_observed          2652
_reflns_number_total             2652
_reflns_observed_criterion       I>0
_cod_data_source_file            bs1044.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/\s^2^(F)^2^' 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^(F)^2^'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1808.6(4)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2007312