用态和蒙特卡罗组态相互作用逼近精确的超极化率
Approaching exact hyperpolarizabilities via sum-over-states Monte Carlo configuration interaction
摘要：
我们建议使用Monte Carlo组态相互作用的紧凑波函数的状态求和计算，以控制的方式接近高阶偶极属性的精确值，直到第二超极化率。我们将这种方法应用于小系统，一般可以与全组态相互作用（FCI）的结果。我们考虑氟化氢与6- 31克的基础上，然后看看结果，包括频率依赖性，在aug-cc-pVDZ的基础上。我们通过使用aug-cc-pVTZ基将一个计算扩展到FCI之外。在aug-cc-pVDZ基组下计算了具有多参考特征的H $_{4}$分子的性质.然后，我们研究这种方法上的一个强多参考系统与一个更大的FCI空间建模一氧化碳的性质与拉伸几何。通过对氖原子aug-cc-pVDZ到aug-cc-pVQZ的计算结果，考察了该方法随基元尺寸增大的行为。最后，我们测试了这种方法是否能在6- 31 g基上再现氧分子前两个态之间极化率的异常变化。
英文摘要：
We propose using sum-over-states calculations with the compact wavefunctions of Monte Carlo configuration interaction to approach accurate values for higher-order dipole properties up to second hyperpolarizabilities in a controlled way. We apply the approach to small systems that can generally be compared with full configuration interaction (FCI) results. We consider hydrogen fluoride with a 6-31g basis and then look at results, including frequency dependent properties, in an aug-cc-pVDZ basis. We extend one calculation beyond FCI by using an aug-cc-pVTZ basis. The properties of an H$_{4}$ molecule with multireference character are calculated in an aug-cc-pVDZ basis. We then investigate this method on a strongly multireference system with a larger FCI space by modelling the properties of carbon monoxide with a stretched geometry. The behavior of the approach with increasing basis size is considered by calculating results for the neon atom using aug-cc-pVDZ to aug-cc-pVQZ. We finally test if the unusual change in polarizability between the first two states of molecular oxygen can be reproduced by this method in a 6-31g basis.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
