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The unexpected binding and superconductivity in SbH4 at high pressure

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 نشر من قبل Defang Duan
 تاريخ النشر 2015
  مجال البحث فيزياء
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The semimetal antimony (Sb) element doped into hydrogen has been performed theoretically to explored high-pressure crystal structure and superconductivity of antimony hydrides. The unexpected stoichiometry $textrm{SbH}_textrm{4}$ with $P6_3/mmc$ symmetry is found to have most negative enthalpy and embody the coexistence of covalent and ionic bonds. It is a metallic phase and stable in the pressure ranges of 127-300 GPa. Furthermore, a superconducting critical temperature ($T_c$) of 106 K is obtained at 150 GPa by employing the Allen-Dynes modified McMillan equation. In addition, an extrusive distinguishing feature is the presence of soft phonon modes, which is primary contribution to the strength of electron-phonon coupling.

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