The Role of Order-Disorder Transitions in the Quest for Molecular Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence Iron(II)-Iron(III) Formate Framework
Laura Cañadillas-Delgado; Oscar Fabelo; J. Alberto Rodríguez-Velamazán; Marie-Hélène Lemée-Cailleau; Sax A. Mason; Emilio Pardo; Francesc Lloret; Jiong-Peng Zhao; Xian-He Bu; Virginie Simonet; Claire V. Colin; Juan Rodríguez-Carvajal; Journal of the American Chemical Society 134 (2012) 19772–19781; doi:10.1021/ja3082457

data_4118945
_publ_contact_author_address
;Instituto de Ciencia de Materiales de Arag\'on, CSIC-Universidad de Zaragoza, 
C/ Pedro Cerbuna 12, E-50009, Zaragoza, Spain.
Institut Laue-Langevin, Grenoble, 
6 rue Jules Horowitz, B.P. 156, 38042 Grenoble Cedex 9, France.
;
_publ_contact_author_email       fabelo@ill.fr
_publ_contact_author_name        'Dr. Oscar Fabelo'
_publ_section_title
;
 The Role of Order-Disorder Transitions in the Quest for Molecular
 Multiferroics: Structural and Magnetic Neutron Studies of a Mixed Valence
 Iron(II)-Iron(III) Formate Framework
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              19772
_journal_page_last               19781
_journal_paper_doi               10.1021/ja3082457
_journal_volume                  134
_journal_year                    2012
_chemical_formula_sum            'C8 H14 Fe2 N O12'
_chemical_formula_weight         427.88
_space_group_IT_number           167
_symmetry_cell_setting           rhombohedral
_symmetry_Int_Tables_number      167
_symmetry_space_group_name_Hall  '-R 3 2"c'
_symmetry_space_group_name_H-M   'R -3 c :H'
_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                120.00
_cell_formula_units_Z            18
_cell_length_a                   14.2600(17)
_cell_length_b                   14.2600(17)
_cell_length_c                   41.443(8)
_cell_measurement_temperature    45(2)
_cell_volume                     7298.3(19)
_computing_cell_refinement       'ILL RAFD19'
_computing_data_collection
;
'DIRAX (Duisenberg, A.J.M.(1992). J. Appl. Cryst. 25, 92-96),
 ILL HKLGEN, MAD'
;
_computing_data_reduction
;
 'ILL RETREAT (Wilkinson, C., Khamis, H.W., Stansfield, R.F.D., McIntyre, G.J.,
 J. Appl. Crystallogr. 1988, 21, 471.)'
;
_computing_molecular_graphics
'PLATON (A.L.Spek, Acta Cryst. 2009, D65, 148-155.)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      45(2)
_diffrn_detector_area_resol_mean '1.56 mm vert. 2.5 mm hor.'
_diffrn_measured_fraction_theta_full 0.910
_diffrn_measured_fraction_theta_max 0.910
_diffrn_measurement_device_type
'D19 position-sensitive detector diffractometer'
_diffrn_measurement_method       'omega step-scans'
_diffrn_radiation_monochromator  'copper 331'
_diffrn_radiation_probe          neutron
_diffrn_radiation_type           neutron
_diffrn_radiation_wavelength     1.16750
_diffrn_reflns_av_R_equivalents  0.0325
_diffrn_reflns_av_sigmaI/netI    0.0249
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       33
_diffrn_reflns_limit_l_min       -62
_diffrn_reflns_number            10926
_diffrn_reflns_theta_full        62.26
_diffrn_reflns_theta_max         62.26
_diffrn_reflns_theta_min         3.15
_diffrn_source                   'neutron source'
_diffrn_source_type              'ILL High Flux Reactor, beam H11'
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  12
_diffrn_standards_number         4
_exptl_absorpt_coefficient_mu    0.150
_exptl_absorpt_correction_T_max  0.8415
_exptl_absorpt_correction_T_min  0.7213
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details
;
ILL programs D19abs and D19abscan
;
_exptl_crystal_colour            Black
_exptl_crystal_density_diffrn    1.752
_exptl_crystal_description       Prism
_exptl_crystal_F_000             1777
_exptl_crystal_size_max          3
_exptl_crystal_size_mid          1
_exptl_crystal_size_min          1
_refine_diff_density_max         1.624
_refine_diff_density_min         -1.955
_refine_diff_density_rms         0.150
_refine_ls_extinction_coef       0.000194(7)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     170
_refine_ls_number_reflns         2705
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_all          0.0453
_refine_ls_R_factor_gt           0.0370
_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^)+(0.0072P)^2^+129.6265P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0676
_refine_ls_wR_factor_ref         0.0703
_reflns_number_gt                2396
_reflns_number_total             2705
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja3082457_si_001.cif
_cod_data_source_block           D19
_cod_original_sg_symbol_H-M      'R -3 c'
_cod_database_code               4118945