An ab initio study of nuclear volume effects for isotope fractionations using two-component relativistic methods

Keisuke Nemoto, Minori Abe*, Junji Seino, Masahiko Hada

*この研究の対応する著者

研究成果: Article査読

10 被引用数 (Scopus)

抄録

We investigate the accuracy of two-component Douglas-Kroll-Hess (DKH) methods in calculations of the nuclear volume term (≡ lnKnv) in the isotope fractionation coefficient. lnKnv is a main term in the chemical equilibrium constant for isotope exchange reactions in heavy element. Previous work based on the four-component method reasonably reproduced experimental lnKnv values of uranium isotope exchange. In this work, we compared uranium reaction lnKnv values obtained from the two-component and four-component methods. We find that both higher-order relativistic interactions and spin-orbit interactions are essential for quantitative description of lnKnv. The best alternative is the infinite-order Douglas-Kroll-Hess method with infinite-order spin-orbit interactions for the one-electron term and atomic-mean-field spin-same-orbit interaction for the two-electron term (IODKH-IOSO-MFSO). This approach provides almost equivalent results for the four-component method, while being 30 times faster. The IODKH-IOSO-MFSO methodology should pave the way toward computing larger and more general molecules beyond the four-component method limits.

本文言語English
ページ(範囲)816-820
ページ数5
ジャーナルJournal of Computational Chemistry
36
11
DOI
出版ステータスPublished - 2015 4 30

ASJC Scopus subject areas

  • 化学 (全般)
  • 計算数学

フィンガープリント

「An ab initio study of nuclear volume effects for isotope fractionations using two-component relativistic methods」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル