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QUILD: QUantum-regions interconnected by local descriptions
| Content Provider | Semantic Scholar |
|---|---|
| Author | Swart, Marcel Bickelhaupt, F. Matthias |
| Copyright Year | 2008 |
| Abstract | A new program for multilevel (QM/QM and/or QM/MM) approaches is presented that is able to combine different computational descriptions for different regions in a transparent and flexible manner. This program, designated QUILD (for QUantum-regions Interconnected by Local Descriptions), uses adapted delocalized coordinates (Int J Quantum Chem 2006, 106, 2536) for efficient geometry optimizations of equilibrium and transition-state structures, where both weak and strong coordinates may be present. The Amsterdam Density Functional (ADF) program is used for providing density functional theory and MM energies and gradients, while an interface to the ORCA program is available for including RHF, MP2, or semiempirical descriptions. The QUILD optimization setup reduces the number of geometry steps needed for the Baker test-set of 30 organic molecules by approximately 30% and for a weakly-bound test-set of 18 molecules by approximately 75% compared with the old-style optimizer in ADF, i.e., a speedup of roughly a factor four. We report two examples of using geometry optimizations with numerical gradients, for spin-orbit relativistic ZORA and for excited-state geometries. Finally, we show examples of its multilevel capabilities for a number of systems, including the multilevel boundary region of amino acid residues, an S(N)2 reaction in the gas-phase and in solvent, and a DNA duplex. |
| Starting Page | 747 |
| Ending Page | 754 |
| Page Count | 8 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://iqc.udg.es/articles/pdf/iqc641.pdf |
| Alternate Webpage(s) | https://www.wikidata.org/entity/Q56880693 |
| PubMed reference number | 17902157v1 |
| Alternate Webpage(s) | https://doi.org/10.1002/jcc.20834 |
| DOI | 10.1002/jcc.20834 |
| Journal | Journal of Computational Chemistry |
| Volume Number | 29 |
| Issue Number | 5 |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Amino Acids Computation DNA computing DSTN gene Density functional theory Description Drug Allergy Duplex (telecommunications) Energy, Physics Excited state Functional theories of grammar Gradient High Density Lipoproteins Mathematical optimization Møller–Plesset perturbation theory Numerical analysis Orcinus orca Preparation QM/MM Semi-empirical quantum chemistry method Speedup TXN protein, human |
| Content Type | Text |
| Resource Type | Article |
