预测化学与固体物理性质的屏蔽杂化泛函新发展

Global-hybrid density functionals have been widely utilized for a wide range of chemical applications. However, the nonlocal Hartree-Fock (HF) exchange is computationally intensive for periodic solid-state systems with plane wave basis sets. Dielectric and correlation effects in solids can be mimicked by dropping the nonlocal exchange terms at long range; in fact the HF approximation with full long-range exchange is unphysical for solids, especially for metals. One way to ameliorate these difficulties while still getting some of the benefits of introducing HF exchange is to use screened-exchange (SX) hybrid functionals, for which only a percentage of HF exchange at short range is added to the local functionals, while the nonlocal HF exchange at long range is screened. However, the currently published SX hybrid functionals cannot satisfy the high accuracy for different kinds of solid-state properties at the same time. In addition, there are few test results for the newly developed SX hybrid functionals. In this study, 1) we will establish a systematic and comprehensive solid-state database, calculate different properties of different kinds of solids using various density functionals, and analyze the trend of developing SX hybrid functionals; 2) we will present a new SX hybrid functional M06-SX based on the recently proposed revM06 family of density functionals. The M06-SX functional is designed to give comparable accuracy in predicting the chemical properties of molecules to the global-hybrid functionals. Meanwhile, it can also be applied for practical calculations of periodic systems owing to its computational efficiency by screening the long-range HF exchange. 3) The newly developed functional will be applied to the calculations of the properties of various solid-state systems and the energies of atoms and molecules to explore its application potentials.

全局杂化泛函已被广泛应用于化学领域，但对平面波基组的周期性固态体系，非局域的Hartree-Fock（HF）交换能计算量过大。而且固体中的介电效应和相关效应可以通过屏蔽长程的非局域交换项来模拟。屏蔽杂化泛函HF交换能只在短程加入，屏蔽了长程的非局域HF交换能，能降低计算量并保持加入HF交换项的优势。然而，目前已发表的屏蔽杂化泛函不能同时满足对不同种类固体性质的高精度，且对新发展的屏蔽杂化泛函的测试结果较少。在本项目中，1）我们将建立系统全面的固体数据库，分析屏蔽杂化泛函的发展方向；2）基于申请人最近提出的revM06系列泛函发展一种新的屏蔽杂化泛函，M06-SX。M06-SX将在预测分子的化学性质方面具有与全局杂化泛函相当的准确性，同时对周期性固体体系的计算效率和准确性都较高。3）将新发展的泛函应用于多种物理和化学体系，探索其应用空间。

全局杂化泛函已被广泛应用于化学领域，但对平面波基组的周期性固态体系，非局域的Hartree-Fock（HF）交换能计算量过大。而且固体中的介电效应和相关效应可以通过屏蔽长程的非局域交换项来模拟。屏蔽杂化泛函HF交换能只在短程加入，屏蔽了长程的非局域HF交换能，能降低计算量并保持加入HF交换项的优势。然而，目前已发表的屏蔽杂化泛函不能同时满足对不同种类固体性质的高精度，且对新发展的屏蔽杂化泛函的测试结果较少。在本项目中，1）我们在revM06-L泛函基础上加入长程屏蔽的Hartree-Fock能量项，发展了新的屏蔽杂化泛函M06-SX；2）建立了固态体系数据库，包括固态体系晶格常数数据集LC68和固态体系带隙数据集BG60；3）测试了6个屏蔽杂化泛函和6个流行的或新发展的局域泛函对固态体系数据集LC68和BG60的表现。研究目标全部完成。此外，我们还进行了其他深入研究。包括1）我们优化了一个名为CF22D的单一杂化泛函，它比大多数现有的非双杂化泛函具有更高的全面化学精度，通过使用灵活的泛函形式，将依赖于密度和已占轨道的全局杂化元不可分离梯度近似与依赖于几何构象的阻尼色散项结合起来。我们通过使用一个大型数据库和性能触发的迭代监督训练优化了这个能量泛函。2）通过虚拟筛选、分子动力学模拟和体外实验发现Mcl-1小分子抑制剂。3）发现SIRT7抑制剂作为肝癌新疗法，化合物2800Z和40569Z作为研究SIRT7生物功能的化学探针的价值，以及针对肝癌的新治疗方案的开发。4）提出了羰基氧化物的双分子反应的三能级策略可用于大气反应动力学等多领域的研究。本项目提出的密度泛函理论方法能应用于化学、物理、生物、材料等多学科领域的理论计算中，为理论与计算化学提供了新工具。方法可通过多个量子化学软件供广大研究者使用。本项目建立的固态体系数据集可以较为客观全面地评价理论计算方法固态体系晶格常数和带隙地预测能力。