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08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Magnetic circular dichroism in real-time time-dependent density functional theory.
K-M Lee1, K Yabana, G F Bertsch
1Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571, Japan.
The Journal of Chemical Physics
|April 19, 2011
Summary
We present a real-time computational method for calculating magnetic circular dichroism (MCD) spectra. This approach accurately predicts spectral features and aids in understanding MCD sum rules for theoretical assessment.
Area of Science:
- Computational Chemistry
- Spectroscopy
- Quantum Mechanics
Background:
- Magnetic Circular Dichroism (MCD) spectroscopy provides valuable insights into electronic structure.
- Accurate theoretical prediction of MCD spectra is crucial for experimental interpretation.
- Existing computational methods face challenges with complex spectra and high excitation energies.
Purpose of the Study:
- To develop and apply a real-space, real-time computational method for calculating MCD spectra.
- To derive and interpret MCD sum rules within the real-time formalism.
- To assess the accuracy of the method by comparing theoretical predictions with experimental data for C(60).
Main Methods:
- Application of adiabatic time-dependent density functional theory (TD-DFT).
- Utilizing a real-space, real-time computational approach.
- Derivation of MCD response formulas and sum rules from time-dependent wave function observables.
Main Results:
- The real-time method is well-suited for calculating overall MCD spectra, especially at higher excitation energies.
- MCD sum rules derived in the real-time formalism are useful for normalization and accuracy assessment.
- Application to C(60) correctly predicts the signs of A and B terms for low-energy excitations, with qualitative agreement in magnitudes.
Conclusions:
- The real-time computational method offers a robust approach for MCD spectral calculations.
- The derived MCD sum rules provide a valuable tool for theoretical validation.
- While showing promise, further refinement is needed for quantitative agreement in spectral magnitudes.
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