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تسجيل مستخدم جديدStability of Metallic Structure in Compressed Solid GeH4
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We study the electronic and lattice dynamical properties of compressed solid germane in the pressure range up to 200 GPa with density functional theory. A stable metallic structure, Aba2, with a base-centered orthorhombic symmetry was found to be the lowest enthalpy phase for pressure from 23 to 177 GPa, suggesting an insulator to metal phase transition around 23 GPa. The Aba2 structure is predicted to have higher superconducting transition temperature than SiH4 reported recently, thus presenting new possibilities for exploring high temperature superconductivity in this hydrogen-rich system.
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Room-temperature superconductivity has been one of the most challenging subjects in modern physics. Recent experiments reported that lanthanum hydride LaH$_{10{pm}x}$ ($x$$<$1) raises a superconducting transition temperature $T_{rm c}$ up to ${sim}$2
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