Spectra calculations electronic circular dichroism

Figure 1 compares TDDFT and experiment for the electronic Circular Dichroism (CD) spectrum of the chiral fullerene Cyg. A total of 240 optically allowed transitions were required to simulate the spectrum. The accuracy is clearly good enough to assign the absolute configuration of Cyg. TDDFT calculations of this size typically take less than a day on low-end personal computers. 

The two principal resonance limits of the theory of ROA are the far-from-resonance (FFR) limit, the original form of the theory of ROA, and the single-electronic-state (SES) limit, for the case of strong resonance between a single excited electronic state and the incident laser radiation. In the case of FFR ROA, ab initio calculations have been carried out for direct comparison with experiment. The SES theory is so simple that the complete SES-ROA spectrum can be predicted from the parent resonance Raman spectrum and the electronic circular dichroism spectrum of the resonant electronic state. 

Basis Sets Correlation Consistent Sets Circular Dichro-ism Electronic Complete Active Space Self-consistent Field (CASSCF) Second-order Perturbation Theory (CASPT2) Configuration Interaction Density Functional Applications Density Functional Theory (DFT), Hartree-Fock (HF), and the Self-consistent Field Electronic Diabatic States Definition, Computation, and Applications ESR Hyperfine Calculations Magnetic Circular Dichroism of rt Systems Non-adiabatic Derivative Couplings Relativistic Theory and Applications Structure Determination by Computer-based Spectrum Interpretation Valence Bond Curve Crossing Models. 

A MINDO/3 method has been used to calculate the electronic structure of polyethylene,127 and comparison has been made with the photoelectron spectrum. Extended Huckel calculations on six fluorinated compounds derived from linear polyethylene have been carried out with the same objective.128 The circular dichroism of unordered polymers has been treated on the basis of time-dependent Hartree theory,129 130 131 and high-resolution inelastic tunnelling spectroscopy of macromolecules has been reported.180... 

Circular Dichroism Electronic Configuration Interaction Semiempirical Calculations Molecular Mechanics Conjugated Systems Spectroscopy Computational Methods Structure Determination by Computer-based Spectrum Interpretation Symmetry in Chemistry. 

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