New high pressure polymorph of theCaSi2compound with Laves structure

Abstract

In the present work, based on first-principles calculations, we show that it is possible to obtain a new high pressure polymorph of the CaSi2compound with a Laves structure. It corresponds to the MgCu2-type (C15) which is one of the three most important Laves phases. We also show that the two other structures, MgNi2- and MgZn2-types are very competitive energetically and are possible candidates for finite temperature investigations.