High-frequency and -field EPR and FDMRS study of the [Fe(H2O)6]2+ ion in ferrous fluorosilicate.
The complex [Fe(H2O)6]SiF6 is one of the most stable and best characterized high-spin Fe(II) salts and as such, is a paradigm for the study of this important transition metal ion. We describe high-frequency and -field electron paramagnetic resonance studies of both pure [Fe(H2O)6]SiF6 and [Zn(H2O)6]SiF6 doped with 8% of Fe(II). In addition, frequency domain magnetic resonance spectroscopy was applied to these samples. High signal-to-noise, high resolution spectra were recorded which allowed an accurate determination of spin Hamiltonian parameters for Fe(II) in each of these two, related, environments. For pure [Fe(H2O)6]SiF6, the following parameters were obtained: D=+11.95(1) cm(-1), E=0.658(4) cm(-1), g=[2.099(4),2.151(5),1.997(3)], along with fourth-order zero-field splitting parameters: B4(0)=17(1)×10(-4) cm(-1) and B4(4)=18(4)×10(-4) cm(-1), which are rarely obtainable by any technique. For the doped complex, D=+13.42(1) cm(-1), E=0.05(1) cm(-1), g=[2.25(1),2.22(1),2.23(1)]. These parameters are in good agreement with those obtained using other techniques. Ligand-field theory was used to analyze the electronic absorption data for [Fe(H2O)6]SiF6 and suggests that the ground state is 5A1, which allows successful use of a spin Hamiltonian model. Density functional theory and unrestricted Hartree-Fock calculations were performed which, in the case of latter, reproduced the spin Hamiltonian parameters very well for the doped complex.
National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA.
J
J
Krzystek
D
D
Smirnov
Christoph
C
Schlegel
Joris
J
van Slageren
Joshua
J
Telser
Andrew
A
Ozarowski
D000465:Algorithms; D003460:Crystallization; D003627:Data Interpretation, Statistical; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005296:Ferrous Compounds / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D007501:Iron / Q000737:chemistry; D011789:Quantum Theory; D017640:Silicates / Q000737:chemistry*; D012824:Silicic Acid / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D019265:Spectroscopy, Near-Infrared
D005296:Ferrous Compounds; D017640:Silicates; D012824:Silicic Acid; C004832:hexafluorosilicate; D007501:Iron; D005459:Fluorides