X-ray Diffraction and EXAFS Studies of Hydroxo-Cu(II) Complexes Based on a Calix[6]arene-N3 Ligand: Evidence for a Mononuclear-Dinuclear Equilibrium Controlled by Supramolecular Features
Guillaume Izzet; Yves M. Frapart; Thierry Prangé; Karine Provost; Alain Michalowicz; Olivia Reinaud; Inorganic Chemistry 44 (2005) 9743–9751; doi:10.1021/ic0511322

data_4310227
_publ_contact_author_address
; Laboratoire de cristallographie et RMN Biologique (UMR 8015-CNRS), 
  4 Av. de l'Observatoire, 75006 Paris, France
;
_publ_contact_author_email       thierry.prange@univ-paris5.fr
_publ_contact_author_fax         '33 1 53739925'
_publ_contact_author_name        'Prof. Thierry Prang\'e'
_publ_contact_author_phone       '33 1 53739663'
_publ_section_title
;
X-ray Diffraction and EXAFS Studies of Hydroxo-Cu(II) Complexes Based on
a Calix[6]arene-N3 Ligand: Evidence for a Mononuclear-Dinuclear
Equilibrium Controlled by Supramolecular Features
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              9743
_journal_page_last               9751
_journal_paper_doi               10.1021/ic0511322
_journal_volume                  44
_journal_year                    2005
_chemical_formula_moiety
;
  2(C84 H108 Cu N6 O7),
  0.714(C H2 Cl2), 0.494(C H2 Cl2), 0.534(C H2 Cl2), 
  0.567(C H2 Cl2), 0.715(C H2 Cl2), 0.89(C4 H10 O),
  2(Cl O4)
;
_chemical_formula_sum            'C174.58 H230.95 Cl8.05 Cu2 N12 O22.89'
_chemical_formula_weight         3276.32
_chemical_name_common
;
Compound 2 - oslla -
;
_chemical_name_systematic
;
  di Hydroxo-Cu(II) Calix[6]arene-tri(O-methyl-imidazole), di-
  perchlorate, solvate: five CH2Cl2, one ether
;
_space_group_IT_number           1
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  'P 1'
_symmetry_space_group_name_H-M   'P 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXH-97
_cell_angle_alpha                69.67(8)
_cell_angle_beta                 80.58(8)
_cell_angle_gamma                64.63(8)
_cell_formula_units_Z            1
_cell_length_a                   15.279(4)
_cell_length_b                   16.130(4)
_cell_length_c                   22.828(4)
_cell_measurement_temperature    193(2)
_cell_volume                     4766(4)
_computing_cell_refinement       'DENZO/HKL, Otwinowski & Minor, 1997)'
_computing_data_collection       'DENZO/HKL, Otwinowski & Minor, 1997)'
_computing_data_reduction        'SCALEPACK/HKL, Otwinowski & Minor, 1997)'
_computing_structure_refinement  'SHELXH-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.918
_diffrn_measured_fraction_theta_max 0.918
_diffrn_measurement_device_type  'MAR RESEARCH 345 Image plate'
_diffrn_measurement_method       rotation
_diffrn_radiation_monochromator  'silicon III'
_diffrn_radiation_source         monochromatic
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.952
_diffrn_reflns_av_R_equivalents  0.0750
_diffrn_reflns_av_sigmaI/netI    0.0259
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            22741
_diffrn_reflns_theta_full        27.37
_diffrn_reflns_theta_max         27.37
_diffrn_reflns_theta_min         2.46
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  120
_diffrn_standards_number         7000
_exptl_absorpt_coefficient_mu    1.043
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    1.141
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1740.13
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.597
_refine_diff_density_min         -0.386
_refine_diff_density_rms         0.085
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.13(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.040
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1810
_refine_ls_number_reflns         8041
_refine_ls_number_restraints     2343
_refine_ls_restrained_S_all      1.021
_refine_ls_R_factor_all          0.0884
_refine_ls_R_factor_gt           0.0762
_refine_ls_shift/su_max          0.019
_refine_ls_shift/su_mean         0.007
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1781P)^2^+5.1989P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2194
_refine_ls_wR_factor_ref         0.2229
_reflns_number_gt                6448
_reflns_number_total             8041
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic0511322si20050708_042913.cif
_cod_data_source_block           oslla
_cod_original_cell_volume        4766(3)
_cod_database_code               4310227
_publ_section_details
;           
Some "Alert A"s remain (resolution too low ..etc) They are due
 to geometric limitations of the MAR RESEACH Image plate 
 during  data collection at the synchrotron place and has no 
 real incidence on the accuracy of the structure 
 (max resolution about 1.1 A, data completness 90 %)
 
 In addition:
-Structure with a large content of solvent.
 This structure is large enough to mimic "protein"
 hydration - hydrogens on water molecules are not visible..etc
-B factors are in the order of what is found in protein atoms
 and false alert on terbutyl groups occurs 
 (Ueq as Compared to Neighbors...)
-Due to the paucity of observed data, restraints were applied on
  all atomic distances and angles, an usual way in macromolecular
  refinements. Some atoms are kept isotropic to avoid refinement
  instabilities.
-Although the structure itself is centrosymmetric, the solvent 
 distribution brakes this centrosymmetry (odd number of solvent
 molecules). Refinements proceed smoothly only in the P1 space 
 group.
;