Acoustic Velocities and Phase Transitions in Molybdenum under Strong Shock Compression

Abstract

We present acoustic velocity data that demonstrate a high-pressure solid-solid phase transition in molybdenum at about 2.1 Mbar and 4100 K. This observation is supported here by first-principles theoretical calculations which predict a zero-temperature bcc\ensuremath{\rightarrow} hcp transition within our experimental pressure range. In addition, our results show the melting transition for shock-compressed Mo at about 3.9 Mbar and 10000 K.