Tetraethyl pyrazine-2,3,5,6-tetracarboxylate
Wang, Yi; Stoeckli-Evans, Helen; IUCrData 1 (2016) x152174–; doi:10.1107/S2414314615021744

data_1542472
_publ_section_title
;
 Tetraethyl pyrazine-2,3,5,6-tetracarboxylate
;
_journal_issue                   1
_journal_name_full               IUCrData
_journal_page_first              x152174
_journal_paper_doi               10.1107/S2414314615021744
_journal_volume                  1
_journal_year                    2016
_chemical_formula_iupac          'C16 H20 N2 O8'
_chemical_formula_moiety         'C16 H20 N2 O8'
_chemical_formula_sum            'C16 H20 N2 O8'
_chemical_formula_weight         368.34
_chemical_name_systematic
;
Tetraethyl pyrazine-2,3,5,6-tetracarboxylate
;
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                81.285(11)
_cell_angle_beta                 82.771(11)
_cell_angle_gamma                77.208(11)
_cell_formula_units_Z            1
_cell_length_a                   5.4194(8)
_cell_length_b                   9.0619(12)
_cell_length_c                   9.4607(13)
_cell_measurement_reflns_used    4119
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      29.54
_cell_measurement_theta_min      2.18
_cell_volume                     445.80(11)
_computing_cell_refinement
;
X-Area (Stoe & Cie, 2009)
;
_computing_data_collection
;
X-Area (Stoe & Cie, 2009)
;
_computing_data_reduction
;
X-RED32 (Stoe & Cie, 2009)
;
_computing_molecular_graphics
;
PLATON (Spek, 2009) and Mercury (Macrae <i>et al.</i>,  2008)
;
_computing_publication_material
;
<i>SHELXL2014/6</i> (Sheldrick, 2015), PLATON (Spek, 2009) and
publcif (Westrip, 2010)
;
_computing_structure_refinement
;
<i>SHELXL2014/6</i> (Sheldrick, 2015)
;
_computing_structure_solution
;
<i>SHELXS2014/6</i> (Sheldrick, 2008)
;
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       '2-circle goniometer'
_diffrn_measurement_device_type  'STOE IPDS 2'
_diffrn_measurement_method       '\f + \w scans'
_diffrn_radiation_monochromator  'plane graphite'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0777
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            6815
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.224
_diffrn_reflns_theta_min         2.188
_exptl_absorpt_coefficient_mu    0.111
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.6503
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(MULABS; Spek, 2009)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.372
_exptl_crystal_description       plate
_exptl_crystal_F_000             194
_exptl_crystal_size_max          0.31
_exptl_crystal_size_mid          0.27
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.263
_refine_diff_density_min         -0.210
_refine_ls_extinction_coef       0.054(10)
_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   0.857
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     121
_refine_ls_number_reflns         2408
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.857
_refine_ls_R_factor_all          0.0837
_refine_ls_R_factor_gt           0.0492
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0654P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1137
_refine_ls_wR_factor_ref         0.1239
_reflns_number_gt                1414
_reflns_number_total             2408
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            sj4001sup1.cif
_cod_data_source_block           I
_cod_depositor_comments          'Adding full bibliography for 1542472.cif.'
_cod_database_code               1542472
_cod_database_fobs_code          1542472
_shelx_hkl_checksum              18329
_shelx_res_checksum              6920
_shelxl_version_number           2014/6