تقرير
Stochastic resolution of identity to CC2 for large systems: excited state properties
| العنوان: | Stochastic resolution of identity to CC2 for large systems: excited state properties |
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| المؤلفون: | Zhao, Chongxiao, Ou, Qi, Lee, Joonho, Dou, Wenjie |
| سنة النشر: | 2023 |
| المجموعة: | Physics (Other) |
| مصطلحات موضوعية: | Physics - Chemical Physics |
| الوصف: | We apply a stochastic resolution of identity approximation (sRI) to the CC2 method for excitation energy calculations. A set of stochastic orbitals are employed to decouple the crucial 4-index electron repulsion integrals and optimize the contraction steps in CC2 response theory. The CC2 response for excitations builds upon sRI-CC2 ground-state calculations, which scales as O(N^3), where N is a measure for the system size. Overall, the current algorithm for excited states also allows a sharp scaling reduction from original O(N^5) to O(N^3). We test the sRI-CC2 for different molecular systems and basis sets, and we show our sRI-CC2 method can accurately reproduce the results of deterministic CC2 approach. Our sRI-CC2 exhibits an experimental scaling of O(N^2.88) for a hydrogen dimer chain, allowing us to calculate systems with nearly thousands of electrons. Comment: 19 pages, 4 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2310.18350 |
| رقم الأكسشن: | edsarx.2310.18350 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |