钒团簇的几何和电子结构——从分子到体相性质的演化

基于密度泛函理论,优化了钒团簇V_n(n=2—9,13,15,19,27,51)的几何结构,通过研究键长、配位数、平均结合能、电离势、电子亲和能、总的态密度和平均磁矩随着尺寸的变化规律,从理论上揭示了n≤9的钒团簇电子结构具有分立特征的分子行为和很强的尺寸效应,13≤n≤19是从分子向体相态结构变化的过渡区域;V₂₇和V₅₁的态密度已趋向于体相的三峰结构,说明它们已接近大块钒的性质 关键词： 钒团簇 密度泛涵理论 电子结构

GEOMETRICAL AND ELECTRONIC STRUCTURES OF VANADIUM CLUSTERS, AND THEIR EVOLUTION FROM MOLECULAR TO BULK PHASE

We have optimized the geometrical structures of the vanadium clusters V_n and discussed their evolution with cluster sizes in the average nearest-neighbor distances, coordination numbers, binding energies, ionization potential, electron affinities, density of states, valence band width, and magnetic moments using the density functional theory.We found that the clusters from V₂ to V₉ have distinctly molecular behaviour with dramatic size variations; V₁₃, V₁₅, and V₁₉ are the transition regions from the molecular features to the bulk structures, and V₂₇ and V₅₁ possess almost the bulk properties.