Calculation and prediction for the hydriding properties of LaNi5-xMx alloys

The enthalpy of formation and hydrogen content for hydrides of LaNi5 - xMx (M stands for Mn, Fe, Co, Ni, Al, Ga, Ge and Si) alloys have been investiga ted by the stepwise regression method and atomic parameters. The models use d for quantitative prediction of the enthalpy of formation and hydrogen con tent are presented. The main factors affecting hydrogen content and the ent halpy of formation are given. It is demonstrated that the plateau pressure can be expressed as a semi-empirical model, which consists of the atomic si ze parameter and the average electronegativity difference at; well as the a verage of the outer electron number of alloys. It is found that the amount of absorbed hydrogen of LaNi5 - xMx alloys is controlled by electronegativi ty difference, atomic size, electron concentration and charge-radii ratio. (C) 1999 Published by Elsevier Science S.A. All rights reserved.