Functional formamidines: pyridine substituents make an exception in the usual doubly hydrogen-bonded formamidine dimer
Petitjean, Anne; Xing, Liyan; Wang, Ruiyao; CrystEngComm 12 (2010) 1397–; doi:10.1039/b922918c

data_7212233
_publ_section_title
;
 Functional formamidines: pyridine substituents make an exception in the
 usual doubly hydrogen-bonded formamidine dimer
;
_journal_issue                   5
_journal_name_full               CrystEngComm
_journal_page_first              1397
_journal_paper_doi               10.1039/b922918c
_journal_volume                  12
_journal_year                    2010
_chemical_formula_sum            'C11 H10 N4'
_chemical_formula_weight         198.23
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   11.7861(5)
_cell_length_b                   7.2290(3)
_cell_length_c                   23.2069(9)
_cell_measurement_reflns_used    3781
_cell_measurement_temperature    180(2)
_cell_measurement_theta_max      27.14
_cell_measurement_theta_min      3.42
_cell_volume                     1977.27(14)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0156
_diffrn_reflns_av_sigmaI/netI    0.0142
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_number            6973
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         2.46
_exptl_absorpt_coefficient_mu    0.085
_exptl_absorpt_correction_T_max  0.9831
_exptl_absorpt_correction_T_min  0.9790
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.332
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             832
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.183
_refine_diff_density_min         -0.147
_refine_diff_density_rms         0.037
_refine_ls_extinction_coef       0.0100(12)
_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   1.059
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     141
_refine_ls_number_reflns         1938
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0357
_refine_ls_R_factor_gt           0.0322
_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^)+(0.0488P)^2^+0.4557P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0855
_refine_ls_wR_factor_ref         0.0893
_reflns_number_gt                1764
_reflns_number_total             1938
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b922918c.txt
_cod_data_source_block           ap11
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      Pbca
_cod_database_code               7212233