A [2 x 2] nickel(ii) grid and a copper(ii) square result from differing binding modes of a pyrazine-based diamide ligand.
Klingele, Julia; Boas, John F.; Pilbrow, John R.; Moubaraki, Boujemaa; Murray, Keith S.; Berry, Kevin J.; Hunter, Keith A.; Jameson, Geoffrey B.; Boyd, Peter D. W.; Brooker, Sally; Dalton transactions (Cambridge, England : 2003)  (2007) 633–645; doi:10.1039/b614796h

data_7005018
_publ_section_title
;
 A [2 x 2] nickel(ii) grid and a copper(ii) square result from
 differing binding modes of a pyrazine-based diamide ligand.
;
_journal_issue                   6
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              633
_journal_page_last               645
_journal_paper_doi               10.1039/b614796h
_journal_year                    2007
_chemical_formula_sum            'C20 H20 N6 O2'
_chemical_formula_weight         376.42
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_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                 93.204(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.0400(2)
_cell_length_b                   20.6432(6)
_cell_length_c                   17.8496(2)
_cell_measurement_reflns_used    3019
_cell_measurement_temperature    83(2)
_cell_measurement_theta_max      25.7
_cell_measurement_theta_min      1.5
_cell_volume                     1854.20(9)
_computing_cell_refinement       'SAINT (Siemens, 1995)'
_computing_data_collection       'SMART (Siemens, 1995)'
_computing_data_reduction        'SAINT (Siemens, 1995)'
_computing_molecular_graphics    'XP in SHELXTL'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      83(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker SMART area detector'
_diffrn_measurement_method       '\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  0.0765
_diffrn_reflns_av_sigmaI/netI    0.0924
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            10187
_diffrn_reflns_theta_full        25.69
_diffrn_reflns_theta_max         25.69
_diffrn_reflns_theta_min         1.51
_exptl_absorpt_coefficient_mu    0.092
_exptl_absorpt_correction_T_max  1.00
_exptl_absorpt_correction_T_min  0.79
_exptl_absorpt_correction_type   'Semi-empirical (SADABS)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.348
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.256
_refine_diff_density_min         -0.279
_refine_diff_density_rms         0.063
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.063
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     261
_refine_ls_number_reflns         3494
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.063
_refine_ls_R_factor_all          0.1226
_refine_ls_R_factor_gt           0.0604
_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^)+(0.0416P)^2^+0.6889P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1066
_refine_ls_wR_factor_ref         0.1315
_reflns_number_gt                2135
_reflns_number_total             3494
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b614796h.txt
_cod_data_source_block           h2l6d
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)/n
_cod_database_code               7005018