论文部分内容阅读
激发态电子结构计算是理论与计算化学领域中的重要问题.本文测试了密度矩阵重正化群理论的state specific激发态算法,并在Pariser-Parr-Pople(PPP)模型下以并苯体系和聚乙炔体系为例对state specific算法和传统的态平均激发态算法进行了比较.计算结果表明,state specific算法可以正确地跟踪较低的激发态,并能得到比态平均算法更精确的能量本征值;在高激发态的计算过程中,state specific算法可能出现收敛于错误本征态的问题.
The calculation of excited-state electronic structure is an important issue in theoretical and computational chemistry.This paper tests the state-specific excited state algorithm of density matrix renormalization group theory, and uses the Pariser-Parr-Pople (PPP) Polyacetylene system is used as an example to compare the state specific algorithm and the traditional state-averaged excited state algorithm.Results show that the state specific algorithm can correctly track the lower excited states and obtain more precise energy than the state-averaged algorithm In the process of calculating the high-excited states, the state specific algorithm may converge to the problem of the wrong eigenstates.