GPU-based implementations of the noniterative regularized-CCSD(T) corrections: applications to strongly correlated systems
JOURNAL OF CHEMICAL THEORY AND COMPUTATION(2011)
摘要
The details of the graphical processing unit (GPU) implementation of the most computationally intensive (T)-part of the recently introduced regularized CCSD(T) (Reg-CCSD(T)) method [Kowalski, K.; Valley, M. J. Chem. Phys. 2009, 131, No. 234107] for calculating electronic energies of strongly correlated systems are discussed. Parallel tests performed for several molecular systems show very good scalability of the triples part of the Reg-CCSD(T) approach. We also discuss the performance of the Reg-CCSD(T) GPU implementation as a function of the parameters defining the partitioning of the spinorbital domain (tiling structure). The accuracy of the Reg-CCSD(T) method is illustrated on three examples: the methyfluoride molecule, dissociation of dodecane, and open-shell Spiro cation (5,5'(4H,4H')-spirobi[cydopenta[c]pyrrole] 2,2',6,6'-tetrahydro cation), which is a frequently used model to study electron transfer processes. It is demonstrated that a simple regularization of the cluster amplitudes used in the noniterative corrections accounting for the effect of triply excited configurations significantly improves the accuracies of ground-state energies in the presence of strong quasidegeneracy effects. For methylfluoride, we compare the Reg-CCSD(T) results with the CR-CC(2,3) and CCSDT energies, whereas for Spiro cation we compare Reg-CCSD(T) results with the energies obtained with completely renormalized CCSD(T) method. Performance tests for the Spiro, dodecane, and uracil molecules are also discussed.
更多查看译文
关键词
electron transfer
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络