A new tetrakis-substituted pyrazine carboxylic acid, 3,3',3'',3'''-{[pyrazine-2,3,5,6-tetrayltetrakis(methylene)]tetrakis(sulfanediyl)}tetrapropionic acid: crystal structures of two triclinic polymorphs and of two potassium‒organic frameworks
Pacifico, Jessica; Stoeckli-Evans, Helen; Acta Crystallographica Section E 77 (2021) 480–490; doi:10.1107/S2056989021003479

data_2243803
_publ_section_title
;
 A new tetrakis-substituted pyrazine carboxylic acid,
 3,3',3'',3'''-{[pyrazine-2,3,5,6-tetrayltetrakis(methylene)]tetrakis(sulfanediyl)}tetrapropionic
 acid: crystal structures of two triclinic polymorphs and of two
 potassium--organic frameworks
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              480
_journal_page_last               490
_journal_paper_doi               10.1107/S2056989021003479
_journal_volume                  77
_journal_year                    2021
_chemical_formula_iupac          '[K2 (C20 H26 N2 O8 S4 )]'
_chemical_formula_moiety         '2K +, (C20 H26 N2 O8 S4) 2-'
_chemical_formula_sum            'C20 H26 K2 N2 O8 S4'
_chemical_formula_weight         628.87
_chemical_name_systematic
Poly[(\m-3,3'-{[(3,6-bis{[(2-carboxyethyl)sulfanyl]methyl}pyrazine-2,5-diyl)bis(methylene)]bis(sulfanediyl)}dipropionato)dipotassium]
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2018/3
_cell_angle_alpha                90
_cell_angle_beta                 94.753(6)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   27.908(2)
_cell_length_b                   8.2916(6)
_cell_length_c                   11.3035(9)
_cell_measurement_reflns_used    20250
_cell_measurement_temperature    153(2)
_cell_measurement_theta_max      29.60
_cell_measurement_theta_min      1.80
_cell_volume                     2606.7(3)
_computing_cell_refinement
;
X-Area (Stoe & Cie, 2002)
;
_computing_data_collection
;
X-Area (Stoe & Cie, 2002)
;
_computing_data_reduction
;
X-RED32 (Stoe & Cie, 2002)
;
_computing_molecular_graphics
;
PLATON (Spek, 2020) and Mercury (Macrae <i>et al.</i>,  2020)
;
_computing_publication_material
;
SHELXL-2018/3 (Sheldrick, 2015), PLATON (Spek, 2020) and
publcif (Westrip, 2010)
;
_computing_structure_refinement
;
SHELXL-2018/3 (Sheldrick, 2015)
;
_computing_structure_solution
;
SHELXS-97 (Sheldrick, 2008)
;
_diffrn_ambient_temperature      153(2)
_diffrn_detector                 'image plate (34 cm diameter)'
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.993
_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  0.0420
_diffrn_reflns_av_unetI/netI     0.0222
_diffrn_reflns_limit_h_max       38
_diffrn_reflns_limit_h_min       -38
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            19423
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.584
_diffrn_reflns_theta_min         2.563
_diffrn_source
'sealed X-ray tube, 12 x 0.4 mm long-fine focus'
_exptl_absorpt_coefficient_mu    0.732
_exptl_absorpt_correction_T_max  0.8033
_exptl_absorpt_correction_T_min  0.4164
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
(<i>ShxAbs</i>; Spek, 2020)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.602
_exptl_crystal_description       plate
_exptl_crystal_F_000             1304
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.500
_exptl_crystal_size_min          0.050
_refine_diff_density_max         0.755
_refine_diff_density_min         -0.514
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     167
_refine_ls_number_reflns         3646
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0430
_refine_ls_R_factor_gt           0.0366
_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^)+(0.0541P)^2^+3.5192P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0993
_refine_ls_wR_factor_ref         0.1034
_reflns_number_gt                3175
_reflns_number_total             3646
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            pk2656sup1.cif
_cod_data_source_block           K2H2L1
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2243803
_shelx_estimated_absorpt_t_min   0.711
_shelx_estimated_absorpt_t_max   0.964
_shelx_hkl_checksum              72493
_shelx_res_checksum              34119
_cod_database_fobs_code 2243803