Superconducting high pressure phase of germane
Guoying Gao1, Artem R Oganov, Aitor Bergara
1National Lab of Superhard Materials, Jilin University, Changchun 130012, P. R. China.
Physical Review Letters
|October 15, 2008
Summary
High-pressure germane (GeH4) forms a novel metallic monoclinic structure. This structure is stable above 196 GPa and exhibits a high superconducting critical temperature of 64 K.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Germane (GeH4) is a simple hydride with complex high-pressure phase behavior.
- Understanding these phases is crucial for exploring novel material properties under extreme conditions.
Purpose of the Study:
- To investigate the high-pressure crystal structures of germane (GeH4).
- To predict the superconducting properties of predicted high-pressure germane phases.
Main Methods:
- Ab initio evolutionary methodology was employed to predict high-pressure structures.
- Enthalpy calculations determined phase stability and decomposition pressures.
- Perturbative linear-response calculations assessed electron-phonon coupling and superconductivity.
Main Results:
- A novel metallic monoclinic C2/c structure of germane was identified.
- This structure is stable in the pressure range of 0-196 GPa.
- A high superconducting critical temperature (Tc) of 64 K was predicted at 220 GPa, with a large electron-phonon coupling parameter (λ = 1.12).
Conclusions:
- The C2/c structure represents a new high-pressure phase of germane.
- Germane exhibits significant potential for high-temperature superconductivity under pressure.
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