Analytical Gradients of Hartree鈥揊ock Exchange with Density Fitting Approximations
详细信息 查看全文
- 作者：Jonas Bostr枚m ; Francesco Aquilante ; Thomas Bondo Pedersen ; Roland Lindh
- 刊名：Journal of Chemical Theory and Computation
- 出版年：2013
- 出版时间：January 8, 2013
- 年：2013
- 卷：9
- 期：1
- 页码：204-212
- 全文大小：358K
- 年卷期：v.9,no.1(January 8, 2013)
- ISSN：1549-9626
文摘
We extend the local exchange (LK) algorithm [Aquilante, F.; Pedersen, T. B.; Lindh, R. J. Chem. Phys.2007, 126, 194106] to the calculation of analytical gradients with density fitting. We discuss the features of the screening procedure and demonstrate the possible advantages of using this formulation, which is easily interfaced to a standard integral-direct gradient code. With auxiliary basis sets obtained from Cholesky decomposition of atomic or molecular integral blocks with a decomposition threshold of 10鈥?Eh, typical errors due to the density fitting in bond lengths, bond angles, and dihedral angles are 0.1 pm, 0.1掳, and 0.5掳, respectively. The overall speedup of geometry optimizations is about 1 order of magnitude for atomic natural-orbital-type basis sets but much less pronounced for correlation-consistent basis sets.