Tuning Anisotropy Barriers in a Family of Tetrairon(III) Single-Molecule Magnets with an S = 5 Ground State
Stefania Accorsi; Anne-Laure Barra; Andrea Caneschi; Guillaume Chastanet; Andrea Cornia; Antonio C. Fabretti; Dante Gatteschi; Cecilia Mortalò; Emiliano Olivieri; Francesca Parenti; Patrick Rosa; Roberta Sessoli; Lorenzo Sorace; Wolfgang Wernsdorfer; Laura Zobbi; Journal of the American Chemical Society 128 (2006) 4742–4755; doi:10.1021/ja0576381

data_4110512
_publ_section_title
;
 Tuning Anisotropy Barriers in a Family of Tetrairon(III) Single-Molecule
 Magnets with an S = 5 Ground State
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              4742
_journal_page_last               4755
_journal_paper_doi               10.1021/ja0576381
_journal_volume                  128
_journal_year                    2006
_chemical_formula_moiety         'C80 H144 Fe4 O18'
_chemical_formula_sum            'C80 H144 Fe4 O18'
_chemical_formula_weight         1617.35
_space_group_IT_number           148
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'SHELXL-97 (Sheldrick, 1997)'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            6
_cell_length_a                   16.4332(2)
_cell_length_b                   16.4332(2)
_cell_length_c                   57.6317(9)
_cell_measurement_temperature    100(2)
_cell_volume                     13478.3(3)
_computing_cell_refinement       'Bruker-Nonius X8APEX package'
_computing_data_collection       'Bruker-Nonius X8APEX package'
_computing_data_reduction        'Bruker-Nonius X8APEX package'
_computing_molecular_graphics    'ORTEP3 (Farrugia, 1997)'
_computing_publication_material  'WINGX v1.64.02 (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR92 (Altomare, 1993)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.989
_diffrn_measured_fraction_theta_max 0.989
_diffrn_measurement_device_type  'Bruker X8APEX four-circle diffractometer'
_diffrn_measurement_method       'phi and omega 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  0.0303
_diffrn_reflns_av_sigmaI/netI    0.0371
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       68
_diffrn_reflns_limit_l_min       -62
_diffrn_reflns_number            19850
_diffrn_reflns_theta_full        25.05
_diffrn_reflns_theta_max         25.05
_diffrn_reflns_theta_min         1.47
_exptl_absorpt_coefficient_mu    0.692
_exptl_absorpt_correction_T_max  0.95
_exptl_absorpt_correction_T_min  0.84
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS - Bruker Nonius area detector scaling 
and absorption correction - V2.10'
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.196
_exptl_crystal_description       'flat hexagons'
_exptl_crystal_F_000             5232
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.08
_refine_diff_density_max         2.802
_refine_diff_density_min         -0.355
_refine_diff_density_rms         0.097
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.059
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     377
_refine_ls_number_reflns         5271
_refine_ls_number_restraints     80
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0806
_refine_ls_R_factor_gt           0.0648
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1288P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1586
_refine_ls_wR_factor_ref         0.1759
_reflns_number_gt                4294
_reflns_number_total             5271
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja0576381si20051109_124008.cif
_cod_data_source_block           fe4tbu_2_work2
_cod_original_sg_symbol_H-M      'R -3'
_cod_database_code               4110512