Four-stranded coordination helices containing silver-adenine (purine) metallaquartets.
Purohit, Chandra Shekhar; Mishra, Ashutosh Kumar; Verma, Sandeep; Inorganic chemistry 46 (2007) 8493–8495; doi:10.1021/ic701465d

data_4339571
_publ_section_title
;
 Four-stranded coordination helices containing silver-adenine (purine)
 metallaquartets.
;
_journal_issue                   21
_journal_name_full               'Inorganic chemistry'
_journal_page_first              8493
_journal_page_last               8495
_journal_paper_doi               10.1021/ic701465d
_journal_volume                  46
_journal_year                    2007
_chemical_formula_moiety         'C8 H7 Ag Cl N5 O4'
_chemical_formula_sum            'C8.5 H7 Ag Cl N5 O4'
_chemical_formula_weight         386.51
_chemical_name_common            '6-chloro 9-allyl purine silver nitrate'
_space_group_IT_number           43
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      43
_symmetry_space_group_name_Hall  'F 2 -2d'
_symmetry_space_group_name_H-M   'F d d 2'
_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            16
_cell_length_a                   24.7086(19)
_cell_length_b                   26.937(2)
_cell_length_c                   7.2010(5)
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.3
_cell_measurement_theta_min      2.3
_cell_volume                     4792.8(6)
_computing_cell_refinement       'SMART 5.628 (Bruker, 2003)'
_computing_data_collection       'SMART 5.628 (Bruker, 2003)'
_computing_data_reduction        'SAINT+ 6.45  (Bruker, 2003)'
_computing_molecular_graphics    'diamond 3.1d'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    Sir92
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area Detector'
_diffrn_measurement_method       'CCD area Detector'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0343
_diffrn_reflns_av_sigmaI/netI    0.0405
_diffrn_reflns_limit_h_max       32
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       35
_diffrn_reflns_limit_k_min       -34
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            7731
_diffrn_reflns_theta_full        28.32
_diffrn_reflns_theta_max         28.32
_diffrn_reflns_theta_min         2.24
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    1.926
_exptl_absorpt_correction_T_max  0.7855
_exptl_absorpt_correction_T_min  0.7284
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North et al., 1968)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.143
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rectangular
_exptl_crystal_F_000             3024
_exptl_crystal_size_max          0.21
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.12
_refine_diff_density_max         1.007
_refine_diff_density_min         -1.066
_refine_diff_density_rms         0.192
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.05(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.235
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     177
_refine_ls_number_reflns         2883
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.234
_refine_ls_R_factor_all          0.0523
_refine_ls_R_factor_gt           0.0361
_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^)+(0.0000P)^2^+229.1535P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0742
_refine_ls_wR_factor_ref         0.1201
_reflns_number_gt                2656
_reflns_number_total             2883
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic701465d-file001.cif
_cod_data_source_block           SV_3
_cod_original_formula_sum        'C8.50 H7 Ag Cl N5 O4'
_cod_database_code               4339571