.png){kind=icon}
返回
Stochastic Multiconfigurational Self-Consistent Field Theory
.png){kind=icon}
OA
AI
DOI：10.1021/acs.jctc.5b00917.png)
.png){kind=icon}
.png){kind=icon}
分享.png){kind=icon}
收藏
摘要
En 中文
The multiconfigurational self-consistent field theory is considered the standard starting point for almost all multireference approaches required for strongly correlated molecular problems. The limitation of the approach is generally given by the number of strongly correlated orbitals in the molecule, since its cost will grow exponentially with this number. We present a new multiconfigurational self-consistent field approach, wherein linear determinant coefficients of a multiconfigurational wave function are optimized via the stochastic full configuration interaction quantum Monte Carlo technique at greatly reduced computational cost, with nonlinear orbital rotation parameters updated variationally based on this sampled wave function. This extends this approach to strongly correlated systems with far larger active spaces than it is possible to treat via conventional means. By comparison with this traditional approach, we demonstrate that the introduction of stochastic noise in both the determinant amplitudes and the gradient and Hessian of the orbital rotations does not preclude robust and reliable convergence of the orbital optimization. It can even improve the ability to avoid convergence to local minima in the orbital space, and therefore aid in finding variationally lower-energy solutions. We consider the effect on the convergence of the orbitals as the number of walkers and the sampling time within the active space increases, as well as the effect on the final energy and error. The scope of the new protocol is demonstrated with a study of the increasingly strongly correlated electronic structure in a series of polycyclic aromatic hydrocarbons, up to the large coronene molecule in a complete active space of 24 it electrons in 24 orbitals, requiring only modest computational resources.
Keyword:
CHARACTERIZING UNPAIRED ELECTRONS
POLYCYCLIC AROMATIC-HYDROCARBONS
2ND-ORDER MCSCF THEORY
ACTIVE SPACE CONCEPT
RELATIVISTIC TREATMENT
CORRELATION-ENERGY
WAVE-FUNCTIONS
GROUND-STATE
SCF METHOD
MC-SCF
AI总结
对已上传原文的论文进行重点信息的提取，主要内容包括：简要概述、研究摘要、背景介绍、关键亮点、图文解析、展望与总结。
期刊
IF:
5.5
论文数:
1.1W
被引数:
5.4W
机构
引用论文
分享收藏Effect of the humidity in the ionic mobility in reduced air-density低空气密度下湿度对离子迁移率的影响.png)
1998 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.98CH36257)
1998 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.98CH36257)IF0
PREAI
分享收藏Efficient and stable orbital-searching algorithm for the configuration interaction method and its application to quantum impurity problemsPHYSICAL REVIEW BOAAI
PHYSICAL REVIEW BIF3.7
OAAI分享收藏Exergetic Investigation of a R1234yf Automotive Air Conditioning System with Internal Heat Exchanger
OAAI
OAAI分享收藏
查看更多内容