New methods for non-linear spectroscopy of molecules in complex environments by combination of coupled-cluster and polarizable embedding approaches

南加州大学的安娜克雷洛夫得到了化学理论、模型和计算方法项目的一个奖项的支持，该项目旨在开发强大而准确的理论方法和计算工具，用于模拟分子与光相互作用时的性质。 该奖项由高级网络基础设施部门的计算和数据支持科学与工程项目共同资助。 Krylov和她的研究小组对非线性光学（NLO）特性感兴趣。 NLO特性在诸如微制造、3D光学数据存储和纳米光刻、超快电光调制和切换、生物成像、光动力疗法以及各种其他纳米生物光子学应用的新技术中被利用。用于解释实验光谱的新工具和用于具有匹配特定应用的特性的新材料的计算机设计的新工具预计将影响NLO特性的基础和应用研究（例如生物成像和分子电子学）。 通过广泛使用的Q-Chem和Spartan软件包，从这项研究中产生的计算机软件可供更广泛的研究界使用。 一旦成熟，该软件将作为开源代码分发。本研究的重点是复杂环境中的开壳物种和分子。拟议的发展利用了上一个供资期开展的工作，其中包括制定形式和实施双光子吸收（2 PA）以及耦合团簇（CC）和运动方程（EOM）系列方法中静态和动态极化率的电子因子计算。 目前工作的主要重点是开发形式和代码：（i）通过有效碎片势方法包括环境（溶剂，分子固体，蛋白质）的影响;和（ii）在EOM-CC框架内的高阶非线性光学性质，如三光子吸收矩和超极化率。新方法的计划应用包括非线性光谱学的基本方面的研究，例如：（i）NLO性质的（非）局部性的程度和这些性质在可极化嵌入方案中计算的收敛性相对于QM区域的大小;（二）溶剂的静电扰动和极化响应与离域激发态贡献的相对重要性（如电荷转移到溶剂状态）;和（iii）电子相关性对非线性光学性质的影响，重点是开壳层系统。教授克雷洛夫是一个积极的贡献者，在科学和工程项目的妇女在南加州大学和超越。她继续维护和发展？？女性在理论和计算化学，材料科学和生物化学？？网页，促进妇女在这些领域的研究。

Anna Krylov of the University of Southern California is supported by an award from the Chemical Theory, Models and Computational Methods program to develop robust and accurate theoretical methods and computational tools for modeling properties of molecules when they interact with light. This award is cofunded by the Computational and Data-Enabled Science and Engineering program in the Division of Advanced Cyberinfrastructure. Krylov and her research group are interested in properties known as non-linear optical (NLO) properties. NLO properties are exploited in novel technologies such as microfabrication, 3D optical data storage and nanolithography, ultra-fast electro-optic modulation and switching, bioimaging, photodynamic therapies, and a variety of other nano-bio-photonics applications. The new tools for interpretation of experimental spectra and for the in silico design of new materials with properties matching particular application are expected to impact both fundamental and applied research (such as bioimaging and molecular electronics) on NLO properties. Computer software generated from this research are made available to the broader research community through the widely-used Q-Chem and Spartan package. Once mature, the software is distributed as open-source code. The emphasis of this research is on open-shell species and molecules in complex environments. The proposed developments capitalize on the work conducted in the previous funding period, which included developing formalisms and implementing calculations of electronic factors for two-photon absorption (2PA) and static and dynamic polarizabilities within the coupled-cluster (CC) and equation-of-motion (EOM) family of methods. The main thrust the current work is to develop the formalisms and codes: (i) to include the effect of the environment (solvent, molecular solids, proteins) via the Effective Fragment Potential method; and (ii) for higher-order NLO properties within the EOM-CC framework, such as three-photon absorption moments and hyperpolarizabilities. The planned applications of the new methods include investigations of fundamental aspects of non-linear spectroscopy, such as: (i) the extent of (non)-locality of NLO properties and the convergence of these properties computed within polarizable embedding schemes with respect to the size of the QM region; (ii) the relative importance of the electrostatic perturbation and polarization response of the solvent versus the contribution from delocalized excited states (such as charge transfer to solvent states); and (iii) the effect of electron correlation on NLO properties, with an emphasis on open-shell systems.will be distributed as open source, similarly to our tensor library and other Q-CHEM modules. Professor Krylov is an active contributor to the Women in Science and Engineering program at USC and beyond. She continues to maintain and develop the ??Women in Theoretical and Computational Chemistry, Material Science, and Biochemistry?? webpage, promoting research by women in these areas.