Počet záznamů: 1
Perturbative universal state-selective correction for state-specific multi-reference coupled cluster methods
- 1.
SYSNO ASEP 0464674 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Perturbative universal state-selective correction for state-specific multi-reference coupled cluster methods Tvůrce(i) Brabec, Jiří (UFCH-W) RID, ORCID
Banik, Subrata (UFCH-W)
Kowalski, K. (US)
Pittner, Jiří (UFCH-W) RID, ORCIDZdroj.dok. Journal of Chemical Physics. - : AIP Publishing - ISSN 0021-9606
Roč. 145, č. 16 (2016), s. 164106Poč.str. 11 s. Jazyk dok. eng - angličtina Země vyd. US - Spojené státy americké Klíč. slova INCOMPLETE MODEL SPACES ; BRILLOUIN-WIGNER ; HILBERT-SPACE Vědní obor RIV CF - Fyzikální chemie a teoretická chemie CEP LH13117 GA MŠMT - Ministerstvo školství, mládeže a tělovýchovy GAP208/11/2222 GA ČR - Grantová agentura ČR Institucionální podpora UFCH-W - RVO:61388955 UT WOS 000387586200011 EID SCOPUS 84993953620 DOI 10.1063/1.4965826 Anotace In this work, we report an extension of our previous development of the universal state-selective (USS) multireference coupled-cluster (MRCC) formalism. It was shown [Brabec et al., J. Chem. Phys. 136, 124102 (2012)] and [Banik et al., J. Chem. Phys. 142, 114106 (2015)] that the USS(2) approach significantly improves the accuracy of Brillouin-Wigner and Mukherjee MRCC formulations, however, the numerical and storage costs associated with calculating highly excited intermediates pose a significant challenge, which can restrict the applicability of the USS(2) method. Therefore, we introduce a perturbative variant of the USS(2) approach (USS(pt)), which substantially reduces numerical overhead of the full USS(2) correction while preserving its accuracy. Since the new USS(pt) implementation calculates the triple and quadruple projections in on-the-fly manner, the memory bottleneck associated with the need of storing expensive recursive intermediates is entirely eliminated. On the example of several benchmark systems, we demonstrate accuracies of USS(pt) and USS(2) approaches and their efficiency in describing quasidegenerate electronic states. It is also shown that the USS(pt) method significantly alleviates problems associated with the lack of invariance of MRCC theories upon the rotation of active orbitals. Pracoviště Ústav fyzikální chemie J.Heyrovského Kontakt Michaela Knapová, michaela.knapova@jh-inst.cas.cz, Tel.: 266 053 196 Rok sběru 2017
Počet záznamů: 1