Tensor-factorization for higher excitation order Coupled-Cluster amplitudes for calculating ground-state energy. Automatic code generation

用于计算基态能量的更高激发阶耦合簇振幅的张量分解。

• 批准号: 189789310
• 负责人: Dr. Daniel Kats
• 金额: --
• 依托单位: Centre for Computational Chemistry
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/189789310?language=en
• 关键词: Tensor; factorization; higher; excitation; order

We will develop a new approach to electronic structure theory based on tensor-factorization of coupled-cluster amplitudes. Coupled-cluster methods have become a standard tool for ab-initio calculations of energies and properties of molecular systems. But even with efficient local implementations it is hardly possible to calculate large molecules beyond the level of coupled-cluster theory with singles, doubles and a perturbative triples correction (CCSD(T)) for ground-state energies. The main problems are the large amount of memory needed to store ground-state amplitudes in iterative procedures (in local formulations even the perturbative triples have to be calculated iteratively) and high effort needed for efficient implementation of these methods. In this project a new tensor-factorization technique will be applied on the coupled-cluster amplitudes beyond CCSD(T) and tested for accuracy and performance. The number of resulting amplitudes will be rather small and this quantities are then much easier to handle. An automatic code generator is essential for efficient and fast implementation of these methods and will be a part of this project. The new methods will make it possible to calculate highly accurate ground-state energies, which are needed e.g. in thermochemistry and studies of chemical reactivity.

我们将发展一种新的方法，电子结构理论的基础上张量因式分解的耦合集团振幅。耦合团簇方法已成为从头计算分子体系能量和性质的标准工具。但是，即使有有效的本地实现，它几乎是不可能的计算大分子超出耦合团簇理论的水平与单，双和微扰三重校正（CCSD（T））的基态能量。主要的问题是大量的内存需要存储在迭代过程中的基态振幅（在当地的配方，甚至微扰三重必须迭代计算）和高的努力需要有效地实施这些方法。在这个项目中，一种新的张量分解技术将被应用于CCSD（T）之外的耦合簇振幅，并测试其精度和性能。结果振幅的数量将相当小，并且这个量因此更容易处理。一个自动代码生成器是有效和快速实现这些方法必不可少的，将是这个项目的一部分。新方法将使计算高精度基态能量成为可能，这在热化学和化学反应性研究中是必需的。