Low-energy dielectric screening in Pd and PdHx systems. (21st January 2015)

• Record Type: Journal Article
• Authors: Silkin, V M; Nazarov, V U; Chernov, I P; Sklyadneva, I Yu; Chulkov, E V
• Is Part Of: Journal of physics. Volume 27:Number 5(2015)
• Publication Date: 2015-01-21
• Subjects: palladium -- palladium hydrides -- collective electronic excitations; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/27/5/055501
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Modifications in dielectric properties of palladium upon absorption of hydrogen are investigated theoretically in the low-energy (0–2 eV) region. The calculations were performed with full inclusion of the electronic band structure obtained within a self-consistent pseudopotential approach. In particular, we trace the evolution of the acoustic-like plasmon (AP) found previously in clean Pd with increasing hydrogen concentration. It exists in PdH x up to the hydrogen content x corresponding to the complete filling of the 4 d Pd-derived energy bands because of the presence of two kinds of carriers at the Fermi surface. At higher H concentration the AP disappears since only one kind of carrier within the sp -like energy band exists at the Fermi level. Additionally, we investigate the spatial distribution inside the crystal of a potential caused by a time-dependent external perturbation and observe drastic modifications in the screening properties in the PdH x systems with energy and with hydrogen concentration.