2024-03-29T06:43:16Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/2078342020-05-04T07:27:29Zcom_10261_115com_10261_3col_10261_494
2020-04-16T10:03:02Z
urn:hdl:10261/207834
Ab initio study of possible metastable occupation of tetrahedral sites in Palladium Hydride compounds
Meninno, Antonella
Errea, Ion
European Research Council
European Commission
Superconductivity
Anharmonicity
High temperature
Trabajo presentado en el 57th European High Pressure Research Group Meeting on High Pressure Science and Technology ( EHPRG 2019), celebrado en Praga (República Checa), del 1 al 6 de septiembre de 2019
Palladium hydrides are one of the rare examples of
superconducting hydrides at ambient pressure. Even if
their critical temperature is around 10 K, they are
fascinating superconductors because of their inverse
isotope effect: the palladium compound has a larger
critical temperature than the hydrogen compound, in
clear contradiction with standard electron-phonon
superconductors. As shown by Errea et al.[1], this
anomalous behavior is induced by the large
anharmonicity of the hydrogen vibrations in the
octahedral sites they occupy.
In recent times, in a controversial paper[2], high
temperature superconductivity was observed in PdH
compounds. The authors of the paper measure traces of
superconductivity as high as at 54K for PdH if this
compound is obtained through fast cooling in the
synthesis. If the compound is obtained with slow cooling
no superconductivity is observed. Their conclusion is
that superconductivity depends strongly on the sites
occupied by hydrogen atoms.
In this work we present first principles calculations
including anharmonic effects within the stochastic selfconsistent harmonic approximation (SSCHA)[3] in order
to unveil the possible existence of dynamically stable
structures with full or partial occupation of tetrahedral
sites, which may be metastable. We discuss the
implications of these possible structures in
superconductivity.
2020-04-16T10:03:02Z
2020-04-16T10:03:02Z
2019-09-01
2020-04-16T10:03:02Z
póster de congreso
57th EHPRG (2019)
http://hdl.handle.net/10261/207834
http://dx.doi.org/10.13039/501100000781
http://dx.doi.org/10.13039/501100000780
Sí
info:eu-repo/grantAgreement/EC/H2020/802533
openAccess