(1. 四川理工学院 材料与化学工程系，自贡 643000；
2. 重庆师范大学 功能材料实验室，重庆 400047)
摘 要: 利用电荷自洽离散变分Xα方法计算Al、Mg合金化对VH2电子结构的影响。研究表明：在VH中加入金属Al以后，H原子的净电荷都减少，V原子的部分净电荷增加部分净电荷减少。V—H键间既有离子性相互作用，又有共价性相互作用；V—H键之间的相互作用减弱，氢容易被释放出来，从而改善了吸放氢性能；Al和Mg合金化以后，V和H原子的净电荷都减少，V—H键间的共价性相互作用增强；V—H键间的相互作用增加，有利于增加贮氢量，不利于改善吸放氢性能。
关键字: 氢化物VH2；合金化；离散变分Xα方法
（1. Department of Material and Chemical Engineering, Sichuan University of Science and Engineering,
Zigong 643000, China;
2. Functional Material Laboratory, Chongqing Normal University, Chongqing 400047, China）
Abstract: The effect of Mg and Al alloying on the electronic structure of VH2 was calculated by the self-consistent charge discrete variational Xα(SCC-DV-Xα) method. The calculated results indicate that when Al is added into VH2, the net charge of H decreases absolutely, on the other hand, the net charge of V decreases and increases partially. Both ionic and covalent interaction exist between V and H. With this interaction weakening, the hydrogen is easy to be released. So the property of absorbing and releasing of H is developed. When Mg alloys on VH2, the net charge of both H and V decreases and the covalent interaction of bond V-H strengthens. So it is advantage to raise the quantity of hydrogen storage, but it is disadvantage to improve the property of absorbing and releasing of hydrogen.
Key words: hydride VH2; alloying; self-consistent charge discrete variational Xα method
