Liquid Silane at High Pressure

Compression of SiH₄ has been suggested as a possible route to achieving metallic hydrogen by way of chemical pre-compression [1]. The structures of crystalline silane and its metallization have been studied extensively, leading to several proposed solid-solid phases at high pressure and the onset of the dissociation of the tetrahedral molecules above 60 GPa. These works have focused on transitions up to room temperature while little is known about the liquid phases of silane. Here we report results from first principles on the electronic and structural transitions in compressed liquid SiH₄predicting a rich fluid phase diagram. Comparison between the solid and liquid phases, which exhibit both similarities and differences, are discussed.