Nuclear magnetic resonance study of the electronic structure and hydrogen diffusion in the random bcc VyTa1-y-H(D) system

被引：2

作者：

Sibirtsev, DS ^{[1
]}

Cherepanov, YG ^{[1
]}

Skripov, AV ^{[1
]}

机构：

[1] Russian Acad Sci, Inst Met Phys, Urals Branch, Sverdlovsk 620219, Russia

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 1998年 / 278卷 / 1-2期

基金：

俄罗斯基础研究基金会;

关键词：

hydrogen in metals; alloys; nuclear magnetic resonance; diffusion;

D O I：

10.1016/S0925-8388(98)00598-2

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：

Nuclear magnetic resonance measurements of the H-1, D-2 and V-51 spin-lattice relaxation rates and the V-51 Knight shifts in the random b.c.c. VyTa1-yHx(D-x) system (0.25 less than or equal to y less than or equal to 0.85, 0.07 less than or equal to x less than or equal to 0.4) have been performed in the temperature range 11-430 K. The relaxation data are analyzed to obtain the parameters of H(D) diffusion which is governed by a distribution of activation energies. In different y ranges the dependencies of the average activation energy (E) over bar(a) on hydrogen concentration are found to differ qualitatively. Comparison of the parameters of H and D diffusion in the samples of nearly the same composition shows that there is a distinct isotope effect: (E) over bar(a)(D)>($) over bar(a)(H). The behaviour of the density of electron states at the Fermi level as a function of y and x is discussed on the basis of the measured values of the V-51 Knight shifts and the electronic (Korringa) contributions to the spin-lattice relaxation rate. (C) 1998 Elsevier Science S.A. All rights reserved.

引用

页码：21 / 28

页数：8