The Tetracyanopyrazinide Dimer Dianion, [TCNP]22-. 2-Electron 8-Center Bonding
Juan J. Novoa; Peter W. Stephens; Mahika Weerasekare; William W. Shum; Joel S. Miller; Journal of the American Chemical Society 131 (2009) 9070–9075; doi:10.1021/ja902790q

data_4104626
_publ_contact_author_address
;
Department of Physics & Astronomy
Stony Brook University
Stony Brook, NY 11794-3800
;
_publ_contact_author_email       peter.stephens@stonybrook.edu
_publ_contact_author_name        'Peter W. Stephens'
_publ_section_title
;
 The Tetracyanopyrazinide Dimer Dianion, [TCNP]22-. 2-Electron 8-Center
 Bonding
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9070
_journal_page_last               9075
_journal_paper_doi               10.1021/ja902790q
_journal_volume                  131
_journal_year                    2009
_chemical_formula_structural     'C20 H12 Cr N6'
_chemical_formula_sum            'C20 H12 Cr N6'
_chemical_formula_weight         388.3
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_cell_angle_alpha                90
_cell_angle_beta                 95.327(1)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   9.3374(2)
_cell_length_b                   10.8037(2)
_cell_length_c                   17.3964(4)
_cell_measurement_temperature    296
_cell_volume                     1747.34(6)
_computing_cell_refinement       TOPAS
_computing_data_collection       SPEC
_computing_molecular_graphics    Mercury
_computing_structure_refinement  TOPAS
_computing_structure_solution    TOPAS
_diffrn_ambient_temperature      296
_diffrn_detector                 'NaI scintillation counter'
_diffrn_detector_type            Canberra
_diffrn_measurement_device_type  'Huber diffractometer'
_diffrn_radiation_monochromator  'Si(111) double reflection monochromator'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.69862
_diffrn_source                   synchrotron
_exptl_absorpt_correction_type   none
_pd_block_diffractogram_id       TCMP_dimer_profile
_pd_char_colour                  'dark purple'
_pd_instr_location
; 
X16C, National Synchrotron Light Source, Brookhaven National Laboratory
;
_pd_meas_2theta_range_inc        0.005
_pd_meas_2theta_range_max        35.000
_pd_meas_2theta_range_min        2.00
_pd_meas_number_of_points        6600
_pd_meas_scan_method             step
_pd_proc_2theta_range_inc        0.005
_pd_proc_2theta_range_max        35.000
_pd_proc_2theta_range_min        4.000
_pd_proc_info_excluded_regions   none
_pd_proc_ls_background_function
;
Chebyshev polynomial of 7th order plus one broad Lorentzian
;
_pd_proc_ls_pref_orient_corr     none
_pd_proc_ls_profile_function
;
Simple_Axial_Model function in TOPAS
;
_pd_proc_ls_prof_R_factor        0.0525
_pd_proc_ls_prof_wR_expected     0.0287
_pd_proc_ls_prof_wR_factor       0.0675
_pd_proc_wavelength              0.69862
_pd_spec_mounting
;
glass capillary(nominal diameter 1mm)
;
_pd_spec_mount_mode              transmission
_pd_spec_shape                   cylinder
_pd_spec_size_axial              8
_pd_spec_size_equat              1
_pd_spec_size_thick              1
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   2.355
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     78
_refine_ls_weighting_details     1/(sigma*sigma)
_refine_ls_weighting_scheme      sigma
_cod_data_source_file            ja902790q_si_001.cif
_cod_data_source_block           CrBz2TCNP
_cod_database_code               4104626
_cod_database_fobs_code          4104626