电荷掺杂和杂原子掺杂聚硅烷的比较性理论研究

COMPARISON THEORETICAL STUDY BETWEEN THE CHARGE DOPED AND THE HETEROATOM

本文利用GAUSSIAN 03程序包中的密度泛函理论,在B3LYP/6-31G(d)水平下,对聚21硅烷、电荷掺杂的聚21硅烷以及杂原子(硼和磷)掺杂的聚21硅烷进行几何全优化,并对它们的几何结构和自旋密度进行了比较性理论研究.结果表明,电荷掺杂能使聚硅烷的Si-Si键长增长,其极子分布几乎遍及了聚21硅烷的整个链;而杂原子(B、P)的掺杂对聚硅烷的影响主要集中在与B、P原子相邻的Si原子上,极子分布仅局域在B、P原子附近的3～5个原子上.

The geometry structures of undoped,charge doped,and heteroatom(B and P) doped oligosilanes(containing 21 Si atoms) are optimized using density functional theory(DFT) at the B3LYP/6-31G(d) level as implemented in GAUSSIAN 03 program.It is found from the calculated results that the charge doping increase almost all the Si—Si bond lengths and the polaron formed by charge doping spreads almost all over the chain length.In contrast,the heteroatom(B,P) doping exerts little influence on the strength of Si—Si bonds,the polaron formed by heteroatom doping localized on only 3～5 atoms.