运用固体与分子经验电子理论(EET),定量分析LaNi5溶氢前后的价电子结构变化.结果表明:LaNi5中,平行于xoy平面内原子间的键合较强,而平行于z轴方向原子间的键合很弱,原子键合呈现明显的各向异性分布.LaNi5H7中,NiH键的键能远大于La-H键,正是通过这两种元素的协调作用,形成中等强度的化学键,有利于可逆的吸放氢反应发生.EET理论给出的电子结构计算结果与第一原理的计算结果相吻.LaNi5溶氢后,平均晶格电子数显著减少,脆性增加,同时考虑到LaNi5中原子键合的各向异性分布,因此该合金反复吸放氢后易粉化.
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