State-Resolved Vibrational Spectra of Fluxional Protonated Water Clusters via Tensor Network States

在化学系（CHE）化学理论、模型和计算方法（CTMC）项目的支持下，Henrik R。位于默塞德的加州大学的拉尔森正在开发新的理论方法，将用于解开质子化水分子团簇中的量子效应。这些团簇是理解水的基本性质的关键，例如它的酸度，这取决于许多复杂的量子相互作用。亨利克河Larsson和他的研究小组将开发旨在实现高效准确模拟质子化水簇的方法，相对于以前的工作，复杂性增加了近一个数量级。在这项研究中开发的方法预计将普遍适用于广泛的领域，包括能源科学，天文学和光化学的广泛类别的量子系统。Larsson博士计划在量子动力学网络内共同组织一个跨学科研讨会，讨论如何开发模拟量子系统的新方法，将来自不同领域的科学界聚集在一起。拉尔森博士计划通过在暑期学校讲课，让早期的职业科学家参与分子量子动力学这一令人兴奋的领域。主要研究者还旨在通过ACS项目种子，让经济困难的高中生和第一代本科生参与与该项目直接相关的研究活动。拉尔森和他在加州大学默塞德的研究小组将开发全维振动量子动力学模拟的方法。他们将开发的方法基于张量网络状态，利用密度矩阵重整化群（DMRG）和多层多构型时间相关Hartree（ML-MCTDH）方法的力量。他们将应用这些新方法来理解有限温度，同位素取代和微溶剂化对质子转移运动和质子化水簇的红外光谱的影响。他们将优化和分析导致对实验光谱知之甚少的高度激发的波函数。集群之间的差异和相似性将通过显式波函数比较和降维模拟进行分析。该计划中开发的方法预计将广泛适用于振动流态的研究之外，例如，将可能是有用的模拟非绝热动力学和计算激发电子states.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

With support from the Chemical Theory, Models and Computational Methods (CTMC) program in the Division of Chemistry (CHE), Henrik R. Larsson of the University of California, Merced is developing new theoretical methods that will be applied to unravel quantum effects in protonated water clusters. These clusters are key to understanding the fundamental properties of water, such as its acidity, which depend on many complex quantum interactions. Henrik R. Larsson and his research group will be developing methods that are designed to enable an efficient and accurate simulation of protonated water clusters with nearly an order of magnitude increase in complexity relative to previous work. The methods developed in this research are expected to be generally applicable to a broad class of quantum systems in a wide range of fields including energy sciences, and astro- and photochemistry. Dr. Larsson plans to co-organize an interdisciplinary workshop within the Quantum Dynamics Network about developing new methods for simulating quantum systems to bring scientific communities from different fields together. Plans are in place for Dr. Larsson to engage early career scientists in the exciting field of molecular quantum dynamics by lecturing at a summer school. The principal investigator also aims to involve economically disadvantaged high school students, through ACS Project Seed, and first generation undergraduate students in research activities that are directly linked to this project.Dr. Henrik R. Larsson and his research group at the University of California, Merced will develop methods for full-dimensional vibrational quantum dynamics simulations. The methods they will develop are based on tensor network states, leveraging the power of the density matrix renormalization group (DMRG) and of the multilayer multi-configurational time-dependent Hartree (ML-MCTDH) method. They will apply these new methods to understanding the effects of finite temperature, isotope substitution and microsolvation on the proton transfer motion and the infrared spectrum of protonated water clusters. They will optimize and analyze highly excited wavefunctions that lead to poorly understood experimental spectra. Differences and similarities between the clusters will be analyzed by means of explicit wavefunction comparisons and by reduced-dimensional simulations. The methods developed in this program are expected to be broadly applicable beyond the study of vibrational fluxional states and, for example, will likely be useful for simulating nonadiabatic dynamics and for computing excited electronic states.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.