Geometry optimizations with spinor-based relativistic coupled-cluster theory

Zheng, Xuechen; Zhang, Chaoqun; Liu, Junzi; Cheng, Lan

doi:10.1063/5.0086281

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Geometry optimizations with spinor-based relativistic coupled-cluster theory

Zheng, Xuechen·Zhang, Chaoqun·Liu, Junzi·Cheng, Lan

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Abstract

Development of analytic gradients for relativistic coupled-cluster singles and doubles augmented with a non-iterative triples [CCSD(T)] method using an all-electron exact two-component Hamiltonian with atomic mean-field spin–orbit integrals (X2CAMF) is reported. This enables efficient CC geometry optimizations with spin–orbit coupling included in orbitals. Here, the applicability of the implementation is demonstrated using benchmark X2CAMF-CCSD(T) calculations of equilibrium structures and harmonic vibrational frequencies for methyl halides, CH 3 X (X = Br, I, and At), as well as calculations of rotational constants and infrared spectrum for RaSH+, a radioactive molecular ion of interest to spectroscopic study.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY coupled-cluster theory geometry optimization infrared spectroscopy molecular geometry relativistic effects rotational spectra spin-orbit coupling

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Zheng, Xuechen, Zhang, Chaoqun, Liu, Junzi, Cheng, Lan. 2022-03-29. Geometry optimizations with spinor-based relativistic coupled-cluster theory. https://doi.org/10.1063/5.0086281

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