Efficient double hybrid density functional theory algorithms for conformational a

构象α的高效双杂化密度泛函理论算法

基本信息

批准号：
8123785
负责人：
JING KONG
金额：
$ 10.12万
依托单位：
Q-CHEM, INC.
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-15 至 2012-09-14
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Double hybrid (DH) density functionals are one of the most promising new developments in quantum mechanical methods for simulating biomolecules. DH functionals have been reported to yield much more accurate intermolecular interaction energies than previous generation functionals. They are therefore on the threshold of becoming widely used. However, there are still practical obstacles blocking widespread use of DH functionals, apart from lack of familiarity to users. This SBIR proposal aims to embrace the opportunity of greater accuracy offered by the DH approach by directly addressing the key known limitations. These limitations and our proposed remedies are as follows. (i) DH functionals are more computationally expensive to evaluate than conventional functionals because the cost scales as the 5th power, rather than the 3rd power of molecular size. We will implement and benchmark a novel 3rd order method for evaluating the DH energy without explicit two-electron integrals. The computational savings for biophysically useful accuracy will be assessed on conformational relative energies. (ii) DH functionals require larger atomic orbital basis sets to yield converged relative energies, but doubling the basis requires 16 times more computation. We will significantly ameliorate this slow convergence by augmenting the basis to explicitly include interelectronic coordinates, via F12 techniques that have proven successful for wave function methods. This first use of F12 methods to evaluate the DH energy will be benchmarked to assess the reduction in basis set size that is possible without sacrificing accuracy for conformational energies and intermolecular interactions. PUBLIC HEALTH RELEVANCE: to implement a new DFT method in a computationally efficient manner. DFT is at the core of molecular modeling and is applied widely in biological research/development and in drug discovery. The improved DFT will significantly increase researchers' quality of work and extend the application scope of DFT.

描述（由申请人提供）：双杂交（DH）密度功能是模拟生物分子的量子机械方法中最有希望的新发展之一。据报道，DH功能比上一代功能产生更准确的分子间相互作用能。因此，它们正处于广泛使用的门槛上。但是，除了对用户缺乏熟悉之外，仍然存在实用的障碍，阻止了DH功能的广泛使用。该SBIR提案旨在通过直接解决关键已知限制来拥抱DH方法提供更高准确性的机会。这些局限性和我们提出的补救措施如下。（i）与常规功能相比，DH功能在计算上的评估价格更高，因为成本量表是第五功率，而不是分子大小的第三功率。我们将实施和基准一种新型的三阶方法，用于评估DH能量，而无需显式两电子积分。生物物理上有用精度的计算节省将在构象相对能量上进行评估。（ii）DH功能需要较大的原子轨道基集以产生收敛的相对能量，但是将基础增加一倍需要增加16倍的计算。我们将通过通过F12技术在波函数方法上成功的F12技术来显着改善这种缓慢的收敛，从而明确地包括互电子坐标。首次使用F12方法来评估DH能量的方法将是基准的，以评估基准大小的减少，而构象能和分子间相互作用的精确度是可能的。公共卫生相关性：以计算有效的方式实施新的DFT方法。 DFT是分子建模的核心，广泛应用于生物学研究/发育和药物发现。改进的DFT将大大提高研究人员的工作质量并扩大DFT的应用范围。