Nuclear Volume Effects on Chemical Reactions

化学反应的核体积效应

• 批准号: 22655006
• 负责人: HADA Masahiko
• 金额: $ 2.18万
• 依托单位: Tokyo Metropolitan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2010
• 资助国家: 日本
• 起止时间: 2010 至 2011
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-22655006/
• 关键词: 相対論的量子化学; 核体積効果; 同位体分別反応; 電子状態理論; 宇宙化学

I consider the nuclear volume effect, a new cause of isotope fractionation, from relativistic molecular orbital theory. Four-component Dirac-Coulomb Hartree-Fock method with Gaussian type nucleus model well reproduces the experimental isotope fractionation factor of uranium isotope exchange reaction. Hence, we could theoretically confirm that nuclear volume difference of isotope really cause the isotope fractionation as the scale of the experiment. I also discuss the relationship of ligand coordination and nuclear volume effect. Since the stronger ligand locates closer to the uranium, it provides larger nuclear volume effect. In atomic isotope spectra, it is known that the field shift(nuclear volume effect in atomic spectra) is proportional to the electron charge density on nucleus. However, this is not clear for molecular system and isotope fractionation factor. Hence I analyze the electron density at the nucleus for all molecules calculated and found that the density and isotopic energy difference show highly linearity. It means the analysis of electron density at the nucleus is also possible for the discussion of isotope fractionation caused by nuclear volume effect.

从相对论分子轨道理论出发，考虑了同位素分馏的一个新原因--核体积效应。四分量Dirac-Coulomb Hartree-Fock方法采用高斯型核模型，较好地再现了铀同位素交换反应的同位素分馏因子。因此，我们可以从理论上证实同位素的核体积差确实导致了实验尺度上的同位素分馏。并讨论了配体配位与核体积效应的关系。由于较强的配体位于更接近铀，它提供了更大的核体积效应。在原子同位素谱中，已知场位移（原子谱中的核体积效应）与原子核上的电子电荷密度成正比。然而，这是不清楚的分子系统和同位素分馏因子。因此，我分析了所有计算分子的核电子密度，发现密度和同位素能量差呈现高度线性。这意味着核内电子密度的分析也可以用来讨论核体积效应引起的同位素分馏。

项目成果

Magnetic properties and excited states in the framework of the infinite-order Douglas-Kroll Method

无限阶道格拉斯-克罗尔方法框架中的磁性和激发态

• 发表时间: 2010
• 作者: 濱島徹;他;山田剛司;M. Hada
• 通讯作者: M. Hada

Expectation values in two-component relativistic theories.

• DOI: 10.1063/1.3397070
• 发表时间: 2010-04
• 期刊: The Journal of chemical physics
• 作者: Junji Seino;Wataru Uesugi;M. Hada

Nuclear Magnetic Shielding Constants in the framework of the infinite-order Douglas-Kroll (IODK) theory

无限阶道格拉斯-克罗尔 (IODK) 理论框架中的核磁屏蔽常数

• 发表时间: 2010
• 作者: 並河英紀;及川哲郎;佐藤真美;鵜浦啓;M.Hada;瀬高渉;M.Hada
• 通讯作者: M.Hada

Magnetic shielding constants calculated by the infinite-order Douglas-Kroll-Hess method with electron-electron relativistic corrections.

• DOI: 10.1063/1.3413529
• 发表时间: 2010-05
• 期刊: The Journal of chemical physics
• 作者: Junji Seino;M. Hada

THEORETICAL STUDY OF NUCLEAR VOLUME EFFECTS IN URANIUM ENRICHMENT

铀浓缩过程中核体积效应的理论研究

• 发表时间: 2010
• 作者: M.Abe;S.Suzuki;Y.Fujii;M.Hada
• 通讯作者: M.Hada