Abstract
We report an implementation of the molecular gradient using the divide-expand-consolidate resolution of the identity second-order Møller-Plesset perturbation theory (DEC-RI-MP2). The new DEC-RI-MP2 gradient method combines the precision control as well as the linear-scaling and massively parallel features of the DEC scheme with efficient evaluations of the gradient contributions using the RI approximation. We further demonstrate that the DEC-RI-MP2 gradient method is capable of calculating molecular gradients for very large molecular systems. A test set of supramolecular complexes containing up to 158 atoms and 1960 contracted basis functions has been employed to demonstrate the general applicability of the DEC-RI-MP2 method and to analyze the errors of the DEC approximation. Moreover, the test set contains molecules of complicated electronic structures and is thus deliberately chosen to stress test the DEC-RI-MP2 gradient implementation. Additionally, as a showcase example the full molecular gradient for insulin (787 atoms and 7604 contracted basis functions) has been evaluated.
| Original language | English |
|---|---|
| Article number | 024106 |
| Journal | Journal of Chemical Physics |
| Volume | 145 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jul 14 2016 |
| Externally published | Yes |
Funding
This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the Department of Energy under Contract No. DE-AC05-00OR22725. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme No. (FP/2007-2013)/ERC Grant Agreement No. 291371. D.B. acknowledges the Marie Curie Individual Fellowship funding for DECOS, Project No. 657514.