Distortion of the fcc lattice in superstoichiometric β-YH2+δ and cubic YH3-η thin films

被引：5
作者：
Carsteanu, AM
Rode, A
Zur, D
Schoenes, J
Borgschulte, A
Westerwaal, R
机构：
[1] Tech Univ Carolo Wilhelmina Braunschweig, Inst Halbleiterphys & Opt, D-38106 Braunschweig, Germany
[2] Vrije Univ Amsterdam, Fac Sci, Div Phys & Astron, NL-1081 Amsterdam, Netherlands
来源：
JOURNAL OF ALLOYS AND COMPOUNDS | 2005年 / 404卷
关键词：
thin films; crystal structure and symmetry; inelastic light scattering;
D O I：
10.1016/j.jallcom.2004.09.091
中图分类号：
O64 [物理化学（理论化学）、化学物理学];
学科分类号：
070304 ; 081704 ;
摘要：
We have monitored with Raman spectroscopy the metal insulator transition of Y films grown on (111) CaF2 substrates and capped with Pd. Characteristic for the gamma phase is a Raman spectrum with nine lines at room temperature. In the stoichiometric beta phase, YH2 shows only one line. In the superstoichiometric beta phase of YH2+delta we find changes in the spectra which are not compatible with a cubic lattice. The Raman mapping image during unloading of a Y film shows a regime of coexistence between the gamma and the superstoichiometric beta phase. The results are compared with measurements on Mg0.1Y0.9Hx which also show a distortion of the cubic lattice. (c) 2005 Elsevier B.V. All rights reserved.
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页码：82 / 84
页数：3
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