Synthesis and Physical Properties of K4[Fe(C5O5)2(H2O)2](HC5O5)2.4H2O (C5O52-= Croconate): A Rare Example of Ferromagnetic Coupling via H-bonds
Matteo Atzori; Elisa Sessini; Flavia Artizzu; Luca Pilia; Angela Serpe; Carlos J. Gómez-García; Carlos Giménez-Saiz; Paola Deplano; Maria Laura Mercuri; Inorganic Chemistry 51 (2012) 5360–5367; doi:10.1021/ic300331e

data_4329119
_publ_section_title
;
 Synthesis and Physical Properties of K4[Fe(C5O5)2(H2O)2](HC5O5)2.4H2O
 (C5O52-= Croconate): A Rare Example of Ferromagnetic Coupling via H-bonds
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              5360
_journal_page_last               5367
_journal_paper_doi               10.1021/ic300331e
_journal_volume                  51
_journal_year                    2012
_chemical_formula_sum            'C20 H14 Fe K4 O26'
_chemical_formula_weight         882.56
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 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                 107.6734(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   10.07260(15)
_cell_length_b                   14.8747(2)
_cell_length_c                   10.1921(2)
_cell_measurement_temperature    180(2)
_cell_volume                     1454.98(4)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_collection       'Collect (Nonius BV, 1997-2000)'
_computing_data_reduction
;
HKL Denzo and Scalepack (Otwinowski & Minor 1997)
;
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare et al., 1997)'
_diffrn_ambient_temperature      180(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  KappaCCD
_diffrn_measurement_method       CCD
_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  0.0813
_diffrn_reflns_av_sigmaI/netI    0.0635
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            25856
_diffrn_reflns_theta_full        31.04
_diffrn_reflns_theta_max         31.04
_diffrn_reflns_theta_min         2.12
_exptl_absorpt_coefficient_mu    1.206
_exptl_absorpt_correction_T_max  0.6966
_exptl_absorpt_correction_T_min  0.6059
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
multi-scan from symmetry-related measurements 
 Sortav (Blessing 1995)
;
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    2.015
_exptl_crystal_description       prism
_exptl_crystal_F_000             888
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.794
_refine_diff_density_min         -0.540
_refine_diff_density_rms         0.112
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.017
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     258
_refine_ls_number_reflns         4643
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.017
_refine_ls_R_factor_all          0.0907
_refine_ls_R_factor_gt           0.0426
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0499P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0904
_refine_ls_wR_factor_ref         0.1075
_reflns_number_gt                2864
_reflns_number_total             4643
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic300331e_si_001.cif
_cod_data_source_block           Fecroc
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4329119