摘要
基于第一性原理,利用密度泛函理论中的广义梯度近似(GGA)对GenFe(n=1—8)团簇进行了结构优化、能量及频率的计算,得到了GenFe(n=1—8)团簇在不同自旋多重度下的平衡构型及其基态结构.结果表明:GenFe混合团簇的平均结合能明显比相应纯锗团簇的平均结合能有所增大,即掺杂Fe原子可以提高锗团簇的稳定性;纯锗团簇的基态除了Ge2为自旋三重态外其他均为单重态,而混合团簇GenFe(n=1—8)的基态均为自旋三重态;对GenFe(n=1—8)团簇的磁性做了较系统的研究,发现团簇总磁矩随团簇尺寸增大基本稳定在2μB(只有Ge8Fe的总磁矩2.391μB较明显地偏离了2μB),另外团簇中Fe原子的磁矩在2.5μB左右振荡.
The geometries, total energies, and frequencies of Gen Fe（ n = 1-8） clusters have been systematically investigated using density functional theory with the generalized gradient approximation, and the equilibrium geometries at different spin multiplicities as well as the ground-state structures have been determined. The calculated results indicate that the average binding energy of the Gen Fe clusters is obviously higher than that of the corresponding pure Gen clusters, which implies that the doping of Fe atom can enhance the stability of the germanium clusters. Except for Ge2 with triplet multiplicity, the ground-state structures of pure germanium clusters are spin singlet; however, the Gen Fe clusters are all triplet. We also systematically studied magnetic properties of Gen Fe clusters and found that the total magnetic moment of cluster stabilizes at about 2μB （except for Ge8 Fe with total moment of 2. 391μB ）, and the magnetic moment of Fe atom stabilizes around 2.5μB.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第5期2596-2602,共7页
Acta Physica Sinica
