Supramolecular metathesis: co-former exchange in co-crystals of pyrazine with (R,R)-, (S,S)-, (R,S)- and (S,S/R,R)-tartaric acid
Braga, Dario; Grepioni, Fabrizia; Lampronti, Giulio I.; CrystEngComm 13 (2011) 3122–; doi:10.1039/c0ce00576b

data_7205664
_publ_section_title
;
 Supramolecular metathesis: co-former exchange in co-crystals of
 pyrazine with (R,R)-, (S,S)-, (R,S)- and (S,S/R,R)-tartaric acid
;
_journal_issue                   9
_journal_name_full               CrystEngComm
_journal_page_first              3122
_journal_paper_doi               10.1039/c0ce00576b
_journal_volume                  13
_journal_year                    2011
_chemical_formula_moiety         'C12 H16 N2 O12'
_chemical_formula_sum            'C6 H8 N O6'
_chemical_formula_weight         190.13
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             2010-05-12T11:09:35-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                81.199(8)
_cell_angle_beta                 83.738(8)
_cell_angle_gamma                88.135(8)
_cell_formula_units_Z            2
_cell_length_a                   4.9168(5)
_cell_length_b                   5.4373(5)
_cell_length_c                   14.7869(14)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     388.28(7)
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.831
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0207
_diffrn_reflns_av_unetI/netI     0.0531
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            2909
_diffrn_reflns_theta_full        25
_diffrn_reflns_theta_max         29.03
_diffrn_reflns_theta_min         2.8
_exptl_absorpt_coefficient_mu    0.149
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.626
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             198
_exptl_crystal_size_max          0.9
_exptl_crystal_size_mid          0.7
_exptl_crystal_size_min          0.6
_refine_diff_density_max         0.294
_refine_diff_density_min         -0.367
_refine_diff_density_rms         0.075
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.826
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     134
_refine_ls_number_reflns         1726
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.826
_refine_ls_R_factor_all          0.0918
_refine_ls_R_factor_gt           0.0568
_refine_ls_shift/su_max          0
_refine_ls_shift/su_mean         0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0918P)^2^+1.0599P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.1808
_reflns_number_gt                1098
_reflns_number_total             1726
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c0ce00576b.txt
_cod_data_source_block           rac2py1
_cod_original_cell_volume        388.28(6)
_cod_database_code               7205664