A tetragonal form of tetra(2-pyridyl)pyrazine (TPPZ)
Greaves, B.; Stoeckli-Evans, H.; Acta Crystallographica Section C 48 (1992) 2269–2271; doi:10.1107/S0108270192009387

data_2000414
_publ_section_title
;
 A tetragonal form of tetra(2-pyridyl)pyrazine (TPPZ)
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2269
_journal_page_last               2271
_journal_paper_doi               10.1107/S0108270192009387
_journal_volume                  48
_journal_year                    1992
_chemical_formula_moiety         'C24 H16 N6'
_chemical_formula_sum            'C24 H16 N6'
_chemical_formula_weight         388.43
_chemical_name_common            tetra(2-pyridyl)pyrazine
_chemical_name_systematic
;
 2,3,4,6-tetra(2-pyridyl)pyrazine
;
_space_group_IT_number           88
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-I 4ad'
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_cell_length_c                   13.2410(10)
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_cell_measurement_temperature    293
_cell_measurement_theta_max      19.00
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_cell_volume                     3881.3(4)
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Stoe AED2 four-circle'
_diffrn_measurement_method       '\w/\q scan b/P/b '
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'xray tube'
_diffrn_radiation_type           'Molybdenum K\a'
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_diffrn_reflns_limit_l_min       0
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_diffrn_reflns_reduction_process Lorentz-polorization
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_diffrn_standards_interval_time  60
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_exptl_absorpt_coefficient_mu    0.08
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_exptl_absorpt_correction_T_min  1.0000
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            transparent
_exptl_crystal_density_diffrn    1.329
_exptl_crystal_description       'large block with many faces'
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_refine_diff_density_max         0.25
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_refine_ls_hydrogen_treatment    'H atoms refined isotropically'
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_refine_ls_R_factor_obs          0.053
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_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_refine_ls_matrix_type' tag value 'full-matrix' was replaced with
'full' value.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Tetragonal' changed to 'tetragonal'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/(\s^2^(F)+0.0040F^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)+0.0040F^2^)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      'I 41/a'
_cod_database_code               2000414