Silane (SiH 4 ) is a promising hydrogen-rich compound for pursing high temperature superconducting. Previous high pressure measurements of Raman, x-ray diffraction and theoretical studies on SiH 4 mainly focused on its polymorphic structures above 50 GPa, while the structure and the stability under lower pressure range are still unclear. Here we report an investigation of condensed SiH 4 by Brillouin scattering measurements at high temperature up to 407 K and high pressure up to 18 GPa. Brillouin scattering frequencies of fluid SiH 4 under compression are obtained under isothermal conditions of 300 K, 359 K and 407 K. The SiH 4 becomes unstable with increasing temperature and subsequently decomposes into silicon and H 2 . We find that compression at room temperature induces two velocity anomalies corresponding to a fluid-solid state transition and a phase IV to phase V transition, respectively. Brillouin scattering sp...

中文翻译：

---

凝聚多晶SiH 4的速度和稳定性：高温高压布里渊研究

硅烷（SiH 4）是一种有前途的富氢化合物，可用于追求高温超导。先前的拉曼高压测量，X射线衍射和对SiH 4的理论研究主要集中在50 GPa以上的多晶型结构，而在较低压力范围内的结构和稳定性仍不清楚。在这里，我们通过布里渊散射测量在高达407 K的高温和高达18 GPa的高压下报告了对凝聚SiH 4的研究。在300 K，359 K和407 K等温条件下，压缩后的流体SiH 4的布里渊散射频率获得。SiH4随着温度的升高变得不稳定，随后分解为硅和H 2。我们发现，室温下的压缩会引起两个速度异常，分别对应于流体-固态过渡和IV相到V相的转变。布里渊散射光谱仪