Quantum Nuclear Dynamics in the Condensed Phase

凝聚态量子核动力学

• 批准号: 1942965
• 金额: --
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1942965
• 关键词: Quantum; Nuclear; Dynamics; Condensed; Phase

The quantum properties of nuclei are determined by the Schroedinger equation, but this equation is much more difficult to solve for nuclei than electrons, with the result that exact quantum dynamics can be obtained from it only for small gas-phase molecules. This project aims to develop approximate methods which will allow quantum dynamics to be simulated in condensed phase systems, such as ice and liquid water. The key idea is that most of the quantum effects in such systems (i.e. zero-point energy and tunnelling) are the result mainly of quantum effects in the Boltzmann statistics; real-time quantum coherences mostly average out. This project will build on a recently developed mixed quantum statistics-classical dynamics method knowns as the 'planetary model', whereby the quantum Boltzmann delocalisation of atomic nuclei is approximated by means of a supplementary 'planet' particle which orbits another particle at the centre of mass of the Boltzmann distribution. This technique allows observable properties such as infrared spectra and neutron-scattering cross sections to be simulated relatively cheaply, and has given very promising results in tests on the infrared spectra of liquid water. This project will focus on extending this methodology to treat non-linear spectra.

原子核的量子性质由薛定谔方程决定，但这个方程对于原子核比对于电子更难求解，因此只能对小的气相分子获得精确的量子动力学。该项目旨在开发近似方法，使量子动力学能够在凝聚相系统（如冰和液态水）中进行模拟。关键的想法是，在这样的系统中的大多数量子效应（即零点能量和隧穿）主要是玻尔兹曼统计中的量子效应的结果;实时量子相干性大多是平均的。该项目将建立在最近开发的混合量子力学-经典动力学方法（称为“行星模型”）的基础上，其中原子核的量子玻尔兹曼离域近似于一个补充的“行星”粒子，该粒子在玻尔兹曼分布的质量中心绕另一个粒子运行。这种技术允许可观察到的属性，如红外光谱和中子散射截面被模拟相对便宜，并给出了非常有前途的结果，在测试液态水的红外光谱。该项目将专注于扩展这种方法来处理非线性光谱。

项目成果

On the "Matsubara heating" of overtone intensities and Fermi splittings.

关于泛音强度和费米分裂的“松原加热”。

• DOI: 10.17863/cam.75774
• 发表时间: 2021
• 作者: Benson R

Which quantum statistics-classical dynamics method is best for water?

• DOI: 10.1039/c9fd00077a
• 发表时间: 2020-01-01
• 期刊: FARADAY DISCUSSIONS
• 影响因子: 3.4
• 作者: Benson, Raz L.;Trenins, George;Althorpe, Stuart C.
• 通讯作者: Althorpe, Stuart C.

Zero-point energy and tunnelling: general discussion.

零点能量和隧道效应：一般讨论。

• DOI: 10.1039/c9fd90075f
• 发表时间: 2019
• 期刊: Faraday discussions
• 影响因子: 3.4
• 作者: Althorpe SC

On the "Matsubara heating" of overtone intensities and Fermi splittings

• DOI: 10.1063/5.0056829
• 发表时间: 2021-09-14
• 期刊: JOURNAL OF CHEMICAL PHYSICS
• 影响因子: 4.4
• 作者: Benson, Raz L.;Althorpe, Stuart C.
• 通讯作者: Althorpe, Stuart C.

Path-integral studies of quantum statistical effects in vibrational spectroscopy

振动光谱中量子统计效应的路径积分研究

• DOI: 10.17863/cam.77080
• 发表时间: 2021
• 作者: Benson R