Full effect of triples in a valence universal multi-reference coupled cluster calculation

被引：17

作者：

Chattopadhyay, S

Mitra, A

Jana, D

Ghosh, P

Sinha, D

机构：

[1] Univ Coll Sci Calcutta, Dept Pure Chem, Kolkata 700009, W Bengal, India

[2] Indian Assoc Cultivat Sci, Dept Phys Chem, Kolkata 700032, W Bengal, India

[3] RK Mahavidyalaya, Dept Chem, Kailasahar 799277, Tripura, India

[4] Tripura Univ, Dept Chem, Suryamaninagar 799130, Tripura, India

来源：

CHEMICAL PHYSICS LETTERS | 2002年 / 361卷 / 3-4期

关键词：

D O I：

10.1016/S0009-2614(02)00974-0

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Full three-electron coupled cluster (CC) operators (triples) along with all singles and doubles are included in a valence universal multi-reference CC calculation to estimate the change in the correlation effect for ionization potential (IP) calculations. We study the vertical IN of two typical systems, N-2 and CO, which go in the opposite direction, i.e., the results were worsened on inclusion of triples when working with relatively smaller basis. However, upon reaching the basis set saturation the expected trend in the results is observed and they are close within 0.1 eV to experimental values almost in every IP. (C) 2002 Published by Elsevier Science B.V.

引用

页码：298 / 306

页数：9

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