Investigation of the phase diagram of selenium by means of Raman spectroscopy

L. Properzi (1) , A. Polian (2) , P. Munsch (2) , A. Di Cicco (1)

1 CNISM, Sezione di Fisica, Scuola di Scienze e Tecnologie, Università di Camerino
2 IMPMC - Institut de minéralogie et de physique des milieux condensés

We report a detailed and systematic Raman scattering investigation of the high pressure - high temperature (350-620 K, 0-20 GPa) phase diagram of elemental selenium starting from its trigonal structure (Se-I). Phase transitions to the tetragonal Se-VII phase were identified by the measured Raman pattern along several isotherms, upon pressurization and depressurization. A wide hysteresis region (∼10-15 GPa) has been observed at 350 K, gradually reducing to about 3GPa at 620 K. These results extend previous scattered determinations of the phase diagram and shifts the Se-I Se-VII transition line up to about 3GPa at lower pressures and ∼150K at lower temperatures

Mots clés: phase transition; selenium; diamond anvil cell; Raman spectroscopy

Domaines: Autre [cond-mat.other]

L. Properzi, A. Polian, P. Munsch, A. Di Cicco. Investigation of the phase diagram of selenium by means of Raman spectroscopy. High Pressure Research, 2013, sous presse. ⟨10.1080/08957959.2013.769048⟩. ⟨hal-00794798⟩