TY - JOUR

T1 - On the rank-reduced relativistic coupled cluster method

AU - Oleynichenko, AV

AU - Rumiantsev, AS

AU - Zaitsevskii, A

AU - Eliav, E

N1 - Times Cited in Web of Science Core Collection: 1 Total Times Cited: 1 Cited Reference Count: 99

PY - 2025

Y1 - 2025

N2 - The efficiency of the Tucker decomposition of amplitude tensors within the single-reference relativistic coupled cluster method with single and double excitations was studied in a series of benchmark calculations for (AuCl)(n) chains, Aun clusters, and the cluster model of solid YbCl2. The 1 kJ/mol level of accuracy for correlation energy estimates of moderate-size systems and typical reaction energies can be achieved with relatively high compression rates of amplitude tensors via rejecting singular values smaller than similar to 10(-4). For the most extensive system studied (the YbCl7 cluster used for modeling of the ytterbium center in the ytterbium dichloride crystal), only similar to 3% of compressed double amplitudes were shown to be significant. Thus, the rank reduction for the relativistic coupled cluster method with single and double theory, improving its computational scaling, is feasible. The advantage (if not necessity) of using the Goldstone diagrammatic technique rather than the "antisymmetrized" Brandow one is underlined. The proposed approach is promising for high-precision modeling of relatively large systems with heavy atoms.

AB - The efficiency of the Tucker decomposition of amplitude tensors within the single-reference relativistic coupled cluster method with single and double excitations was studied in a series of benchmark calculations for (AuCl)(n) chains, Aun clusters, and the cluster model of solid YbCl2. The 1 kJ/mol level of accuracy for correlation energy estimates of moderate-size systems and typical reaction energies can be achieved with relatively high compression rates of amplitude tensors via rejecting singular values smaller than similar to 10(-4). For the most extensive system studied (the YbCl7 cluster used for modeling of the ytterbium center in the ytterbium dichloride crystal), only similar to 3% of compressed double amplitudes were shown to be significant. Thus, the rank reduction for the relativistic coupled cluster method with single and double theory, improving its computational scaling, is feasible. The advantage (if not necessity) of using the Goldstone diagrammatic technique rather than the "antisymmetrized" Brandow one is underlined. The proposed approach is promising for high-precision modeling of relatively large systems with heavy atoms.

KW - SINGULAR-VALUE DECOMPOSITION

KW - ELECTRONIC-STRUCTURE

KW - BASIS-SETS

KW - MOLECULAR CALCULATIONS

KW - TAKAGI FACTORIZATION

KW - IMPLEMENTATION

KW - MODEL

KW - EXCITATIONS

KW - FORMULATION

KW - ENERGIES

U2 - 10.1063/5.0274403

DO - 10.1063/5.0274403

M3 - статья

VL - 163

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 4

ER -