Pressure-induced phase transition of nanocrystalline ZnSe.

C.E.M. Campos (1) , J.C. de Lima (1) , T.A. Grandi (1) , J.P. Itié (2) , A. Polian (2) , A. Michalowicz (3)

1 Departamento de Física [Universidade Federal de Santa Catarina]
2 IMPMC - Institut de minéralogie et de physique des milieux condensés
3 Groupe de Physique Structurale des Molécules et Matériaux

X-ray absorption spectroscopy and Raman experiments were used to follow the semiconductor–metal phase transition of nanocrystalline ZnSe produced by mechanical alloying. The results were used to compare the physical properties of nanometric crystals with those of the standard bulk ones. Due to the crystal size reduction, we observed an increase of the phase-transition pressure. The structural evolution of non-reacted Se with pressure was observed by Raman spectroscopy. This fraction of Se was found to be nanostructured. Thermal annealing showed itself to be an efficient way to manipulate this Se balance, as well as to recover the crystallinity of ZnSe phase.

Mots clés: RAY-ABSORPTION SPECTROSCOPY; X-RAY; AB-INITIO; DIFFRACTION; TRANSFORMATIONS; SCATTERING; SELENIUM; SE

C.E.M. Campos, J.C. de Lima, T.A. Grandi, J.P. Itié, A. Polian, et al.. Pressure-induced phase transition of nanocrystalline ZnSe.. Journal of Physics: Condensed Matter, 2005, 17, pp.5187-5200. ⟨10.1088/0953-8984/17/34/003⟩. ⟨hal-00020186⟩