Development and application of new methods for computing rovibrational spectra and rate constants

计算振动谱和速率常数新方法的开发和应用

• 批准号: RGPIN-2014-05676
• 负责人: Carrington, Tucker
• 金额: $ 6.12万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=646919
• 关键词: Development; application; new; methods; computing

The proposed research is in theoretical chemistry and addresses the motion of atoms in molecules and during reactions. The motion of atoms is easy to calculate and understand if they remain confined very close to an equilibrium geometry. Real chemistry, however, involves large amplitude motion and the making and breaking of bonds. To understand, at a detailed level, the motion of atoms, one must apply the laws of quantum mechanics and solve the Schrödinger equation by representing wavefunctions (functions from which one can calculate all observable properties) in terms of basis functions and using methods of linear algebra to compute observables. The calculations are difficult because the required number of functions and therefore the size of the matrices and vectors to be manipulated is large. I shall develop new ideas for choosing better basis functions, to reduce the number of functions required. From solutions of the Schrödinger equation one can deduce properties of molecules and interpret experimental results. **Our work will provide information necessary for understanding how molecules in the atmosphere absorb and emit radiation, which is important for modelling global warming. Understanding and combating global warming is one of the most important problems of our time. We will study greenhouse gas molecules (ozone, water dimer, methane) and molecules of interest in astrophysics (e.g. CH5+). The greenhouse effect is the rise in temperature that the Earth experiences because gases in the atmosphere trap energy from the sun. A better understanding of greenhouse gases will help us to know how they absorb heat and hence to what extent they are responsible for global warming. Water is an important greenhouse gas and understanding the spectrum of water dimer may be important. This is difficult in the lab because the spectra of water monomer and dimer overlap. The water dimer is also prototype system for understanding hydrogen bonding, which is important in many biological molecules. We shall also study the propargyl radical which is important in combustion. The new techniques we propose developing will enable scientists to understand the motion of atoms in hydrogen bonded molecules (e.g. water dimer). Hydrogen bonds play a very important role in nature. For example, the structure of DNA is determined by hydrogen bonds. Established computational methods for studying the motion of atoms are inadequate for hydrogen bonded molecules. **We will also develop methods to calculate rate constants. To model any complex reacting system one requires rate constants for the elementary reactions that are implicated. The development of accurate, dependable methods to calculate such rate constants would enable one to model (for example) combustion and atmospheric chemistry much more reliably. **The computational methods we develop, both those applied to isolated molecules (spectroscopy) and those applied to reactions (rate constants) relate to the motion of molecules. They will help chemists to analysis and understand laboratory data. Numerical methods we develop may also be useful in other areas of science and engineering. E.g., the equations we use to compute rate constants are also used to study conductivity of molecules. ** In the course of doing this research, HQP will be trained in computational chemistry, numerical analysis and computer science and profit from opportunities provided by numerous international collaborations. Because computational science is important for maintaining health and prosperity it is critical that Canada train scientists to both develop and use modern numerical methods and modern computers.

拟议的研究属于理论化学，涉及分子中和反应过程中的原子运动。如果原子的运动保持非常接近平衡几何形状，则很容易计算和理解，但实际化学涉及大幅运动和。要详细了解原子的运动，必须应用量子力学定律并通过用以下形式表示波函数（可以计算所有可观察性质的函数）来求解薛定谔方程。线性基函数及其使用方法计算可观测值的计算很困难，因为所需的函数数量以及要操作的矩阵和向量的大小很大，我将开发新的想法来选择更好的基函数，以减少所需的函数数量。薛定谔方程的解可以推断出分子的性质并解释实验结果。 **我们的工作将为了解大气中的分子如何吸收和发射辐射提供必要的信息，这对于模拟全球变暖非常重要。我们将研究温室气体分子（臭氧、水二聚体、甲烷）和天体物理学中感兴趣的分子（例如 CH5+）。温室效应是由于气体存在而导致地球温度升高。更好地了解温室气体如何吸收热量，从而了解它们在多大程度上导致了全球变暖，并了解水二聚体的光谱。重要的。这在实验室中很困难，因为水单体和二聚体的光谱重叠，也是理解氢键的原型系统，氢键在许多生物分子中很重要。我们还将研究在燃烧中很重要的炔丙基。我们提出的技术将使科学家能够了解氢键分子（例如水二聚体）中原子的运动，例如，DNA 的结构是由氢键发展确定的。学习**我们还将开发计算速率常数的方法，以模拟任何复杂的反应系统，需要计算所涉及的基本反应的速率常数。这样的速率常数将使人们能够更可靠地模拟（例如）燃烧和大气化学。 **我们开发的计算方法，无论是应用于孤立分子（光谱学）还是应用于与运动相关的反应（速率常数）。他们会的。帮助化学家分析和理解实验室数据。我们开发的数值方法也可能在其他科学和工程领域有用。例如，我们用来计算速率常数的方程也可用于研究分子的电导率。在进行这项研究时，HQP 将接受计算化学、数值分析和计算机科学方面的培训，并从众多国际合作提供的机会中获益，因为计算科学对于维护健康和繁荣非常重要，因此加拿大培训科学家开发和使用现代技术至关重要。数值方法和现代电脑。