Correlation Energies from the Two-Component Random Phase Approximation

详细信息    查看全文

• 作者：Michael Kühn
• 刊名：Journal of Chemical Theory and Computation
• 出版年：2014
• 出版时间：February 11, 2014
• 年：2014
• 卷：10
• 期：2
• 页码：623-633
• 全文大小：385K
• ISSN：1549-9626

文摘

The correlation energy within the two-component random phase approximation accounting for spin鈥搊rbit effects is derived. The resulting plasmon equation is rewritten鈥攁nalogously to the scalar relativistic case鈥攊n terms of the trace of two Hermitian matrices for (Kramers-restricted) closed-shell systems and then represented as an integral over imaginary frequency using the resolution of the identity approximation. The final expression is implemented in the TURBOMOLE program suite. The code is applied to the computation of equilibrium distances and vibrational frequencies of heavy diatomic molecules. The efficiency is demonstrated by calculation of the relative energies of the O_h-, D_4h-, and C_5v-symmetric isomers of Pb₆. Results within the random phase approximation are obtained based on two-component Kohn鈥揝ham reference-state calculations, using effective-core potentials. These values are finally compared to other two-component and scalar relativistic methods, as well as experimental data.