#------------------------------------------------------------------------------
#$Date: 2016-02-19 15:29:56 +0100 (vie 19 de feb de 2016) $
#$Revision: 176759 $
#$URL: svn://www.crystallography.net/cod/cif/2/00/99/2009905.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2009905
loop_
_publ_author_name
'Irngartinger, H.'
'Lichenthäler, J.'
_publ_section_title
;
 Three tetramethylketals of 2,5-distyryl-[1,4]benzoquinones
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1154
_journal_page_last               1156
_journal_paper_doi               10.1107/S0108270193011503
_journal_volume                  50
_journal_year                    1994
_chemical_formula_sum            'C28 H32 O4'
_chemical_formula_weight         432
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_type_scat_source           IntTabIV
_cell_angle_alpha                90.
_cell_angle_beta                 112.18(2)
_cell_angle_gamma                90.
_cell_formula_units_Z            2
_cell_length_a                   11.529(2)
_cell_length_b                   11.867(2)
_cell_length_c                   9.592(2)
_cell_measurement_reflns_used    49
_cell_measurement_temperature    293
_cell_measurement_theta_max      18.04
_cell_measurement_theta_min      9.98
_cell_volume                     1215.2(4)
_diffrn_measurement_device       'Enraf-Nonius CAD-4'
_diffrn_measurement_method       ω/2θ
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.7107
_diffrn_reflns_av_R_equivalents  0.11
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            3136
_diffrn_reflns_theta_max         28
_diffrn_standards_decay_%        17.7
_diffrn_standards_interval_time  60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.18
_exptl_crystal_description       platelets
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.45
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.28
_refine_diff_density_min         -0.10
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_obs   2.30
_refine_ls_hydrogen_treatment    refall
_refine_ls_number_parameters     173
_refine_ls_number_reflns         1192
_refine_ls_R_factor_obs          0.051
_refine_ls_shift/esd_max         0.01
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     'w = 1/[σ(Fₒ)²]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.059
_reflns_number_observed          1192
_reflns_number_total             2919
_reflns_observed_criterion       I>2.5\s(I)
_cod_data_source_file            se1044.cif
_cod_data_source_block           se1044_structure_3_of_3
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/[\s(F~o~)^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(F~o~)^2^]'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 

The authors quote the space group as P 21/n but this yields and chemically
unreasonable polymeric structure, putting it as P 21/c generates the monomeric
species described in the original paper. Hence, we think that the group is
indeed P 21/c

miguel
;
_cod_original_cell_volume        1215.2(8)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2009905
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
O1 .0120(2) -.2094(2) 1.0715(2) .0740(10)
O2 .1189(2) -.0920(2) 1.2647(2) .0680(10)
C1 .0795(2) .0367(2) .9226(3) .0520(10)
C2 .1165(2) -.0472(3) 1.0209(3) .0590(10)
C3 .0440(2) -.0946(2) 1.1077(3) .0560(10)
C4 .1530(2) .0823(3) .8381(3) .0590(10)
C5 .2536(2) .0379(3) .8305(3) .0600(10)
C6 .3325(2) .0831(2) .7524(3) .0520(10)
C7 .3049(2) .1814(2) .6680(3) .0600(10)
C8 .3829(2) .2204(2) .5995(3) .0590(10)
C9 .4901(2) .1632(2) .6105(3) .0520(10)
C10 .5168(2) .0658(3) .6939(3) .0660(10)
C11 .4395(2) .0260(3) .7636(3) .0660(10)
C12 .1097(3) -.2854(3) 1.0896(4) .102(2)
C13 .1500(3) .0178(3) 1.3261(4) .084(2)
C14 .5738(3) .2063(3) .5322(3) .075(2)
H2 .197(2) -.083(2) 1.045(2) .0050(10)
H4 .123(3) .147(3) .778(3) .0100(10)
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_publ_flag
C1 C2 1.326(4) yes
C1 C3' 1.507(4) yes
C2 C3 1.495(5) yes
C1 C4 1.479(4) yes
C4 C5 1.300(4) yes
C5 C6 1.480(4) yes
O1 C3 1.419(4) yes
O2 C3 1.426(3) yes
O1 C12 1.402(4) yes
O2 C13 1.418(4) yes
C6 C7 1.386(4) no
C6 C11 1.376(4) no
C7 C8 1.379(5) no
C8 C9 1.378(4) no
C9 C10 1.373(4) no
C9 C14 1.518(5) no
C10 C11 1.383(5) no
C2 H2 0.96(2) no
C4 H4 0.95(3) no
C5 H5 0.96(2) no
C7 H7 0.87(2) no
C8 H8 0.90(2) no
C10 H10 0.92(3) no
C11 H11 0.98(3) no
C12 H12A 1.00 no
C12 H12C 0.92 no
C12 H12B 0.96 no
C13 H13A 0.94 no
C13 H13B 0.95 no
C13 H13C 0.96 no
C14 H14C 0.90 no
C14 H14A 0.83 no
C14 H14B 0.83 no
