A-Principles of 57Fe Mössbauer effect

Resonant and recoil-free emission and absorption of gamma rays by atoms bound in a solid form

Electric quadrupole interaction

Magnetic Dipole Interaction

B-Mössbauer spectrometer

Mössbauer bench and furnace

C-Preparation of absorbers

D- Spectrum acquisition software

E-Mössbauer effect applications in

Chemistry

Chemical information from isomer shift (IS):
Correlation of IS with oxidation state
Correlation of IS with electron configuration
Correlation of IS with bonding properties

Chemical information from quadrupole splitting (QS)
Effect of aspherical distribution of electrons due to crystal field splitting; electronic structure
Effect of aspherical distribution of electrons due to anisotropic population of molecular orbitals; bonding properties
Effect of aspherical charge distribution due to lowered lattice symmetry; molecular symmetry

Magnetism

Characterization of magnetically-ordered compounds:
Mixed magnetic dipole and electric quadrupole interaction
Isomer shift in complex spectra
Sign of internal magnetic field

Some typical magnetic material characterization studies
Magnetic ordering temperature and type of magnetic ordering
Phase analysis
Phase transition
Site distribution determination
Magnetic structure studies

Comparison of magnetic state depending on penetration depth:
Electron spectrum CEMS (a)
γ-ray spectrum backscattered (b)

Physical Metallurgy

Concepts and principles of spectrum analysis
Important parameters: hyperfine field, isomer shift, quadrupole splitting, component intensities
Statistical calculation on atomic arrangements in Alloys
Interstitial alloys (carbon steel)
Substitutional alloys
Order-disorder alloys
Precipitation
Texture
Diffusion
Amorphous alloys
Nanocrystalline alloys
Nanocomposites
Lunar Geology, Mineralogy and Soils
Lunar Regolith
Lunar “Soil”
Minerals from Lunar rocks
Pyroxene
Plagioclase
Oxidation state of minerals
Soils

Biology

Heme proteins
Low spin ferrous
High spin ferrous
Low spin ferric
High spin ferric
Iron-sulphur proteins

For more information refer to Božidar Cekić and/or Valentin Ivanovski

F-References:

1. Z. D. Dohčević – Mitrović, N. Paunović, M. Radović, Z. V. Popović, B. Matović, B. Cekić, V. Ivanovski
Valence state dependent room-temperature ferromagnetism in Fe-doped ceria nanocrystals
Applied Physics Letters 96, 203104 (2010) 1-3

The room temperature Mössbauer absorption spectra of
a) Ce0.88Fe0.122+O2 and b) Ce0.88Fe0.123+O2

 

2. Hechang Lei, Hyejin Ryu, V. Ivanovski,  J. B. Warren, A. I. Frenkel, B. Cekic, Wei-Guo Yin, and C. Petrovic
Structure and physical properties of the layered iron oxychalcogenide BaFe2Se2O
Phys. Rev. B 86, 195133 – Published 26 November 2012

Mössbauer spectrum of BaFe 2Se 2O at T=294 K. Vertical arrow denotes relative position of peaks with respect to the background. The data were shown by open circles and the fit is given by the red solid line. The doublets of the main (bottom green line) and second phase (top green line; see text) are offset for clarity. Inset shows local coordination of Fe atoms in tetrahedra: The central smallest ball denotes Fe, the medium size ball shows oxygen, and the largest balls show selenium atoms.

 

3. D.Jugović, M.Mitrić, M.Kuzmanović, N.Cvjetičanin, S.Skrapin, B.Cekić, V.Ivanovski, D.Uskoković
Preparation of LiFePO4/C composites by co-precipitation in molten stearic acid
Journal of Power Sources , 196, 10 (2011), 4613-4618

Mössbauer absorption spectra at 294 K of LiFePO4/C composites