Quantum simulations of electron dynamics in aqueous systems

水系统中电子动力学的量子模拟

• 批准号: 1665322
• 负责人: John Herbert
• 金额: $ 45万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1665322&HistoricalAwards=false
• 关键词: Quantum; simulations; electron; dynamics; aqueous

John M. Herbert at The Ohio State University is supported by an award from the Chemical Theory, Models and Computational Methods (CTMC) Program in the Chemistry Division to study the properties and reactivity of solvated electrons and their impacts on biological systems. The interaction of high-energy radiation with water in organisms generates a cascade of highly reactive species that can go on to damage biological material. Amongst these reactive species is the so-called "hydrated" or "solvated" electron. The solvated electron was first discovered more than 50 years ago but detailed structural information is still lacking. This is due in part to its ultra-short lifetime, generally not more than a few microseconds. This poses experimental difficulties, and Herbert is conducting theoretical and computational studies to simulate the structure and properties of the solvated electron and its interaction with the key molecular components of DNA. These studies make contact with a promising new experimental technique which can provide a direct probe of the energy-level structure of liquid systems, but for which theoretical calculations are often required to interpret its results. The ultimate goal of the project is to understand whether these solvated electrons are capable of directly damaging DNA. In order to accomplish this goal, new theoretical and computational tools are being developed. These include new simulation protocols for ab initio molecular dynamics simulations, employing continuum boundary conditions that can be used in conjunction with a Gaussian-orbital-based (rather than plane-wave-based) density functional theory (DFT) code. These developments allow use of accurate hybrid functionals, which are too expensive for plane-wave simulations. In addition, because the deposition of high-energy radiation can generate molecules in excited states, improved versions of time-dependent (TD-)DFT are being developed that can properly describe conical intersections while retaining proper spin (S2) symmetry. These methods are being used, along with "real-time" TD-DFT, to simulate electron injection and removal (photoemission) in aqueous systems.

John M.赫伯特在俄亥俄州州立大学的支持下，从化学理论，模型和计算方法（CTMC）计划在化学部研究溶剂化电子的性质和反应性及其对生物系统的影响奖。高能辐射与生物体内的水相互作用会产生一系列高反应性物质，这些物质可能会继续破坏生物材料。 在这些活性物质中，有一种被称为“水合”或“溶剂化”的电子。溶剂化电子在50多年前首次被发现，但详细的结构信息仍然缺乏。 这部分是由于其极短的寿命，通常不超过几微秒。 这造成了实验上的困难，赫伯特正在进行理论和计算研究，以模拟溶剂化电子的结构和性质及其与DNA关键分子组分的相互作用。 这些研究与一种有前途的新实验技术相联系，这种技术可以直接探测液体系统的能级结构，但通常需要理论计算来解释其结果。 该项目的最终目标是了解这些溶剂化电子是否能够直接破坏DNA。 为了实现这一目标，正在开发新的理论和计算工具。 这些包括从头算分子动力学模拟的新模拟协议，采用连续边界条件，可以与高斯轨道为基础的（而不是平面波为基础的）密度泛函理论（DFT）代码结合使用。 这些发展允许使用精确的混合泛函，这是太昂贵的平面波模拟。 此外，由于高能辐射的沉积可以产生处于激发态的分子，因此正在开发改进版本的时间相关（TD-）DFT，其可以适当地描述锥形交叉，同时保持适当的自旋（S2）对称性。这些方法与“实时”TD-DFT一起沿着使用，以模拟含水系统中的电子注入和去除（光发射）。

项目成果

What Is the Optoelectronic Effect of the Capsule on the Guest Molecule in Aqueous Host/Guest Complexes? A Combined Computational and Spectroscopic Perspective

• DOI: 10.1021/acs.jpcc.7b05522
• 发表时间: 2017-07-20
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY C
• 影响因子: 3.7
• 作者: Bhandari, Srijana;Zheng, Zilong;Dunietz, Barry D.
• 通讯作者: Dunietz, Barry D.

Ab Initio Approach to Femtosecond Stimulated Raman Spectroscopy: Investigating Vibrational Modes Probed in Excited-State Relaxation of Quaterthiophenes

飞秒受激拉曼光谱的从头算方法：研究四噻吩激发态弛豫中探测的振动模式

• DOI: 10.1021/acs.jpca.0c06307
• 发表时间: 2020
• 期刊: The Journal of Physical Chemistry A
• 作者: Dasgupta, Saswata;Herbert, John M.
• 通讯作者: Herbert, John M.

Intrinsically smooth discretisation of Connolly's solvent-excluded molecular surface

• DOI: 10.1080/00268976.2019.1644384
• 发表时间: 2019-07-20
• 期刊: MOLECULAR PHYSICS
• 影响因子: 1.7
• 作者: Lange, Adrian W.;Herbert, John M.;You, Zhi-Qiang
• 通讯作者: You, Zhi-Qiang

Ab Initio Investigation of the Resonance Raman Spectrum of the Hydrated Electron

• DOI: 10.1021/acs.jpcb.9b04895
• 发表时间: 2019-09-26
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY B
• 影响因子: 3.3
• 作者: Dasgupta, Saswata;Rana, Bhaskar;Herbert, John M.
• 通讯作者: Herbert, John M.

Role of hemibonding in the structure and ultraviolet spectroscopy of the aqueous hydroxyl radical

• DOI: 10.1039/d0cp05216g
• 发表时间: 2020-12-21
• 期刊: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
• 影响因子: 3.3
• 作者: Rana, Bhaskar;Herbert, John M.
• 通讯作者: Herbert, John M.