Rare examples of base pairing <i>via</i> a protonated pyridine N atom in two salts of <i>N</i>^2^,<i>N</i>^6^-bis(1,3-dimethylimidazolin-2-ylidene)pyridine-2,6-diamine
Neuba, Adam; Akin, Enver; Herres-Pawlis, Sonja; Flörke, Ulrich; Henkel, Gerald; Acta Crystallographica Section C 64 (2008) m194–m197; doi:10.1107/S0108270108007567

data_2016581
_publ_section_title
;Rare examples of base pairing <i>via</i> a protonated pyridine N atom in two
 salts of
 <i>N</i>^2^,<i>N</i>^6^-bis(1,3-dimethylimidazolin-2-ylidene)pyridine-2,6-diamine
;
_journal_coeditor_code           EM3010
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              m194
_journal_page_last               m197
_journal_paper_doi               10.1107/S0108270108007567
_journal_volume                  64
_journal_year                    2008
_chemical_formula_iupac          'C15 H24 N7 +, Cl O4 -'
_chemical_formula_moiety         'C15 H24 N7 +, Cl O4 -'
_chemical_formula_sum            'C15 H24 Cl N7 O4'
_chemical_formula_weight         401.86
_chemical_name_systematic
;
2,6-bis(1,3-dimethylimidazolin-2-ylideneamino)pyridinium perchlorate
;
_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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                95.979(2)
_cell_angle_beta                 93.739(2)
_cell_angle_gamma                115.549(2)
_cell_formula_units_Z            4
_cell_length_a                   10.4399(11)
_cell_length_b                   12.0367(13)
_cell_length_c                   16.6200(18)
_cell_measurement_reflns_used    1687
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      21.76
_cell_measurement_theta_min      2.37
_cell_volume                     1859.9(3)
_computing_cell_refinement       'SAINT (Bruker, 2002)'
_computing_data_collection       'SMART (Bruker, 2002)'
_computing_data_reduction        'SAINT (Bruker, 2002)'
_computing_molecular_graphics    'SHELXL97 (Sheldrick, 2008)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker SMART APEX'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0925
_diffrn_reflns_av_sigmaI/netI    0.1953
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            18737
_diffrn_reflns_theta_full        28.07
_diffrn_reflns_theta_max         28.07
_diffrn_reflns_theta_min         1.90
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  430
_diffrn_standards_number         1699
_exptl_absorpt_coefficient_mu    0.244
_exptl_absorpt_correction_T_max  0.9595
_exptl_absorpt_correction_T_min  0.9196
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2004)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.435
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.725
_refine_diff_density_min         -0.445
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.828
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     499
_refine_ls_number_reflns         8994
_refine_ls_number_restraints     9
_refine_ls_restrained_S_all      0.835
_refine_ls_R_factor_all          0.1625
_refine_ls_R_factor_gt           0.0644
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0481P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1210
_refine_ls_wR_factor_ref         0.1472
_reflns_number_gt                3686
_reflns_number_total             8994
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            em3010.cif
_cod_data_source_block           I
_cod_database_code               2016581
_cod_database_fobs_code          2016581