Interactions of Model Biomolecules. Benchmark CC Calculations within MOLCAS

0455141 - ÚOCHB 2016 RIV US eng C - Conference Paper (international conference)
Urban, M. - Pitoňák, M. - Neogrády, P. - Dedíková, P. - Hobza, Pavel
Interactions of Model Biomolecules. Benchmark CC Calculations within MOLCAS.
Proceedings of the International Conference of Computational Methods in Sciences and Engineering 2010 (ICCMSE-2010). Melville: AIP Publishing, 2015 - (Simos, T.; Maroulis, G.), s. 178-181. AIP Conference Proceedings, 1642. ISBN 978-0-7354-1282-8. ISSN 0094-243X.
[International Conference of Computational Methods in Sciences and Engineering /8./ (ICCMSE 2010). Psalidi (GR), 03.10.2010-08.10.2010]
Institutional support: RVO:61388963
Keywords : CCSD(T) * OVOS * MOLCAS * Cholesky decomposition * intermolecular interactions * bio molecules
Subject RIV: CF - Physical ; Theoretical Chemistry

We present results using the OVOS approach (Optimized Virtual Orbitals Space) aimed at enhancing the effectiveness of the Coupled Cluster calculations. This approach allows to reduce the total computer time required for large-scale CCSD(T) calculations about ten times when the original full virtual space is reduced to about 50% of its original size without affecting the accuracy. The method is implemented in the MOLCAS computer program. When combined with the Cholesky decomposition of the two-electron integrals and suitable parallelization it allows calculations which were formerly prohibitively too demanding. We focused ourselves to accurate calculations of the hydrogen bonded and the stacking interactions of the model biomolecules. Interaction energies of the formaldehyde, formamide, benzene, and uracil dimers and the three-body contributions in the cytosine - guanine tetramer are presented. Other applications, as the electron affinity of the uracil affected by solvation are also shortly mentioned.
Permanent Link: http://hdl.handle.net/11104/0255789