Structural and electronic properties of compressed selenium and tellurium under high pressure
نویسندگان
چکیده
We investigate the mechanisms of the nonmetal-metal transitions of Se and Te induced by the volume compression both in the solid and liquid states by the density functional method. The volume compression increases the band width and the system transforms from nonmetal to metal phase both in the crystalline Se and Te. When the system has structural disorder, the energy of the anti-bonding level corresponding to long bonds is decreased. This situation induces a nonmetal-to-metal transition in liquid Se under compression at a pressure lower than that for crystalline Se as well as in melting of Te under the normal pressure.
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