The Brownian motion of suspended panicles in EBBA liquid crystal is studied by the Mossbauer technique. Different values are obtained for both the radius of the particles and their mean square displacement in the nematic phase and the isotropic one. This behavior is attributed to anchored, molecular textures on the particles" surfaces. The texture thickness is estimated from the Mossbauer data.

A novel member of the Prussian blue family, cu3Ⅱ [FeⅢ (CN) 6] 2. 3NH3·6H2O, was synthesized, in which NH3 ligands are in stochastic distribution. We present x-ray diffraction data, zero-field-cooled magnetization and field-cooled magnetization curves, Mössbauer spectra with/without an xternal Field of 5 T and a structural model. This Prussian blue analogue displays considerable magnetic hardness below the magnetic transition temperature Tc, which is about 19.8K. The coercive field determined from the magnetization hysteresis loop at 5 K was 2.76 kOe. The copper-iron cyanometallates have potentlal applications in the design of novel magnetic systems.

Some experimental results in the case of anisotropic media are at variance with the Einstein-Stokes formula of Brownian motion and the Singwi-Sjolander model. The dis-agreement comes from the anchor effect. The concept of "pseudoparticle" is introduced in order to retain the Singwi-Sjolander formalism. Mossbauer spectroscopy can be used to estimate the thickness of the anchored liquid-crystalline molecular textures forming on the surface of Brownian particles.

The use of Gev heavy ion beam irradiation has auracted much attention in the field of material science. In the case of garnets, the superexchange inreraction among the maguetie cations in the materials is very sensitive to the electronic stopping power of the beam. The induced microstructure and magnetic propertics of irradiated Ca V Sn: YIG samples have been characterized by means of Mossbauer spectroscopy, high resohution electron microscopy (HREM), X-ray diffraction (XRD), positron annihilation techniques (PAT), vibrating sample magnetometry and ferrimagnetic resonance (FMR). The experimental results are discussed in this paper.