【摘要】 采用FLAPW(全势线性缀加平面波)方法研究了α铀(001)面的弛豫和电子结构.结果表明, α铀表层原子向内收缩2. 9%,次表层和第三层原子分别向外膨胀1. 1%和0. 2%,弛豫能主要由表层和次表层原子的弛豫组成.由于短程屏蔽效应,原子间的相互作用主要局限于近邻原子层之间.相对于体相原子,表层原子由于近邻原子数目的减少, 5f电子轨道波函数重叠、杂化几率降低,能带变窄,定域化性质增强.更多还原

【Abstract】 The full potential linear augmented plane wave method is used to study the relaxation and electronic structure of (001) surface for α-U. The current work predicts a contraction of the topmost layer by 2.9% accompanied by an outward expansion of the second and third layers by 1.1% and 0.2%, respectively. The relaxation of topmost and second layers makes up the largest contribution of relaxation energy. Due to the short-range screening effect, the atomic interaction is mainly limited to adjacent layers. For the surface atoms, due to the reduced nearest neighbors, the contribution to the bonding from 5f electrons is reduced and 5f electrons appear to be more localized.更多还原