Theoretical studies on magnetic circular dichroism by the finite perturbation method with relativistic corrections

Y Honda; M Hada; M Ehara; H Nakatsuji; J Michl

doi:10.1063/1.2080027

Theoretical studies on magnetic circular dichroism by the finite perturbation method with relativistic corrections

J Chem Phys. 2005 Oct 22;123(16):164113. doi: 10.1063/1.2080027.

Authors

Y Honda¹, M Hada, M Ehara, H Nakatsuji, J Michl

Affiliation

¹ Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan. honda@comp.metro-u.ac.jp

PMID: 16268687
DOI: 10.1063/1.2080027

Abstract

A theoretical method for calculating magnetic circular dichroism (MCD) of molecules is presented. We examined the numerical accuracy and the stability of the finite perturbation (FP) method and the sum-over-state (SOS) perturbation method. The relativistic effects are shown to be important for the MCD spectra of molecules containing heavy elements. Calculations using the FP and the SOS methods were carried out for ethylene, para- and ortho-benzoquinone, showing that the FP method is superior to the SOS method, as expected. The relativistic effect was examined using the second-order Douglas-Kroll Hamiltonians for the halogen molecules F2, Cl2, Br2, and I2. The Faraday terms of I2 and Br2 were strongly affected by the relativistic effects, while the effect was negligible for Cl2 and F2.