摘要
计算与分析电子结构对类金刚石薄膜材料的研究尤为重要。本文用第一原理分子动力学模拟,以研究金刚石和石墨的局域态密度和能带结构。第一原理计算赝势平面波法和密度泛函理论(DFT)去计算,电子交换相关能采用广义梯度近似(GGA)去描述,这种方法可以正确无误的预测半导体带隙与尺寸的关系。金刚石的禁带很宽,为绝缘体,Sp3杂化轨道在费米能级附近提供部分能态密度。石墨是零带隙半金属的内部结构根源就在于离域π键,费米能级处的能态密度几乎全部来自p能级的贡献。研究结果预测结构变化和Sp杂化轨道产生的函数关系,是很多物理性质不同的最根本原因,而物理性质的研究则可以最直观的体现这种函数关系,可以更深入地研究金刚石和石墨这两种物质。
The computation and analysis of electron structure are important for diamond-like carbon films.Using ab initio molecular dynamic methods,the paper studied the local density of states（LDOS） and band structure of diamond and graphite.First-principles methods computationally using density function theories（DFT） based on a plane wave pseudo-potential technique,the generalized gradient approximation（GGA） was employed to describe exchange-correlation functional.This kind of method is see fit to right estimate the relationship between semi-conductor band gap and size.Diamond has the forbid bandwidth,and it is an insulator.The sp3 hybridization orbits at the Fermi energy neighborhood provide part ability to the states density.Graphite is zero band gap half metal of the internal structure lie in leaving localπbond,the states density of the Fermi energy neighborhood comes from the contribution of the p energy level almost and all.Analysis reveals the relationship between the structure variety and sp hybridization is a lot of physical property dissimilitudes most basic reason,but the research of the physical property can view this kind of relation, and can go deep into a ground of research diamond and the graphite these two kinds of materials more.
出处
《计算机与应用化学》
CSCD
北大核心
2010年第6期735-738,共4页
Computers and Applied Chemistry
基金
国家自然科学基金资助(10802081)
关键词
类金刚石薄膜
第一性原理
局域态密度
能带结构
diamond-like carbon films
first principles computer simulation
local density of states
band structures
