Mossbauer spectroscopy magnetic hyperfine interaction

The third prominent interaction in iron Mossbauer spectroscopy is the magnetic hyperfine interaction of the Fe nucleus with a local magnetic field. As explained in detail in Chap. 4, it can be probed by performing the Mossbauer experiment in the presence of an applied external magnetic field. 

In order to complete the discussion of magnetic hyperfine interactions in paramagnetic heme proteins as detected by Mossbauer spectroscopy, reference should be made to the work of Champion et al. (58). There the influence of the halides F, Cl, and I on ferric chloroperoxidase was studied. The results presented in this work indicate that halide anions,... 

One less-well-known technique, which has many experimental aspects in common with Mossbauer spectroscopy, deserves special attention at this point, since it gives valuable information about the electric-field gradients and the magnetic hyperfine interactions of radioactive nuclei in solids at ambient conditions and under pressure. In this technique, two y-rays with different energies from two different transitions of an individual nucleus in a radioactive-decay cascade are recorded consecutively. The spatial and temporal perturbation of the emission probability by the hyperfine fields is registered in the corresponding perturbed angular correlation (PAC) spectra. 

The nuclear energy levels are split by Hyperfine Interactions giving rise to quadrupole splitting, magnetic hyperfine interaction and combination of these. This resolution (Ay/y) of in Mossbauer spectroscopy makes it possi-... 

Ni SRPAC of Ni Ferrite The real difficulty for Mossbauer spectroscopy is to study Mossbauer isotopes with high transition energy because of the short lifetime of radioactive source and small Lamb-Mossbauer factor f[>. In the case of Ni, the radioactive source used ( Co) only has 99 min of lifetime, and fLM is 0.02 even in the liquid helium temperature. These make the application of Mossbauer spectroscopy to Ni extremely difficult. As discussed earlier, SRPAC signal is independent to fLM, and the use of SR eliminates the necessity of radioactive sources. It makes SRPAC an ideal technique to study Ni. The first Ni SRPAC experiment was done by Sergueev et al. on Ni-enriched Ni foil to reveal the magnetic hyperfine interactions [18]. Here we report the first application of Ni SRPAC toa Ni-enriched Ni ferrite to reveal the magnetic hyperfine interactions. 

P. Gutlich, et al., Ni-61 Mossbauer-spectroscopy of magnetic hyperfine interaction in nickel spinels,). Chem. Phys. 1984, 8/(3), 1396-1405. 

Another technique widely used for characterizing ferrisilicates is Fe Mossbauer spectroscopy, a very sensitive tool able to differentiate the nuclei in slightly different electronic environments. The electron density of the nuclei, determined by the oxidation state, the coordination number and the type of ligands produce a Mbssbauer isomer shift (IS), while nuclear and magnetic hyperfine interactions are responsible for the form of the spectrum. 

Abstract This chapter describes a general introduction of the Mossbauer spectroscopy. What is the Mossbauer effect and what is the characteristic feature of the Mossbauer spectroscopy These questions are answered briefly in this chapter. Mossbauer spectroscopy is based on recoilless emission and resonant absorption of gamma radiation by atomic nuclei. Since the electric and magnetic hyperfine interactions of Mossbauer probe atom in solids can be described from the Mossbauer spectra, the essence of experiments, the hyperfine interactions and the spectral line shape are discussed. In addition, the experiments and the new resonance technique with synchrotron radiation have been also briefly described. 

In Chap. 5, subsequently, Mossbauer studies on magnetic multilayers and interfaces are explained by Teruya Shinjo and Ko Mibu. Mossbauer spectroscopy has been used as a fundamental analytical tool to characterize various magnetic materials. It is described in this chapter that a magnetic hyperfine interaction observed in a Mossbauer spectrum is information particularly useful to investigate magnetic materials. Examples of studies on various magnetic materials utilizing... 

We have learned from the preceding chapters that the chemical and physical state of a Mossbauer atom in any kind of solid material can be characterized by way of the hyperfine interactions which manifest themselves in the Mossbauer spectrum by the isomer shift and, where relevant, electric quadrupole and/or magnetic dipole splitting of the resonance lines. On the basis of all the parameters obtainable from a Mossbauer spectrum, it is, in most cases, possible to identify unambiguously one or more chemical species of a given Mossbauer atom occurring in the same material. This - usually called phase analysis by Mossbauer spectroscopy - is nondestructive and widely used in various kinds of physicochemical smdies, for example, the studies of... 

Mossbauer spectroscopy senses the hyperfine interactions, which are present at the nucleus of the Mossbauer isotope. The electrical monopole interaction causes the isomer shift and the electric quadrupole interaction leads to the quadrupole splitting, which in the case of Fe causes a two-line Mossbauer pattern. The magnetic dipole interaction leads to a magnetically split six-line pattern (Figure 4). In the following text, these interactions and their deduction from Mossbauer spectra will be discussed. 

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