Nuclear Resonance Scattering Using Synchrotron Radiation Mossbauer Spectroscopy in the Time Domain

Nuclear Resonance Scattering Using Synchrotron Radiation (Mossbauer Spectroscopy in the Time Domain) 

The use of synchrotron radiation overcomes some of the limitations of the conventional technique. The high brilliance of up to 10 ° photons s mm mrad /0.1% bandwidth of energy, and the extremely collimated synchrotron beam lead to a large flux of photons through a very small cross section (0.1-1 mm ). This allows measurements with samples of small volume if isotopi-cally enriched (with the relevant Mossbauer isotope, e.g., Fe). Measurements that were described earlier [4] and that require a polarized Mossbauer source now become experimentally more feasible by making use of the polarization of the synchrotron radiation. Additionally, the energy can be tuned over a wide range. This facilitates measurements with those Mossbauer nuclei for which conventional sources are available but with life times that are too short for most experimental purposes, e.g., 99 min for Co — Ni and 78 h for Ga — Zn. 

NIS of synchrotron radiation yields details of the dynamics of Mossbauer nuclei, while conventional MS yields only limited information in this respect (comprised in the Lamb-Mossbauer factor /). NIS shows some similarity with Resonance Raman- and IR-spectroscopy. The major difference is that, instead of an electronic resonance (Raman and IR), a nuclear resonance is employed (NIS). NIS is site-selective, i.e., only those molecular vibrations that contribute to the overall 

Giitlich et al., Mossbauer Spectroscopy and Transition Metal Chemistry, 

9 Nuclear Resonance Scattering Using Synchrotron Radiation 

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