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Configuration Interaction-Corrected Tamm-Dancoff Approximation: A Time-Dependent Density Functional Method with the
Shaohong L Li1, Aleksandr V Marenich1, Xuefei Xu1
1Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, United States.
The Journal of Physical Chemistry Letters
|August 14, 2015
Summary
A new method, configuration interaction-corrected Tamm-Dancoff approximation (CIC-TDA), accurately models conical intersections in molecules. This advancement improves the dimensionality of intersections, enabling more realistic photochemical simulations.
Area of Science:
- Computational Chemistry
- Quantum Mechanics
- Theoretical Chemistry
Background:
- Linear response (LR) Kohn-Sham (KS) time-dependent density functional theory (TDDFT) is crucial for studying molecular excited states, especially in large systems.
- The Tamm-Dancoff approximation (TDA) to TDDFT offers similar results to KS-LR and improves stability near state intersections.
- Both KS-LR and KS-TDA exhibit incorrect dimensionality (F-1) for conical intersections, hindering accurate photochemical modeling.
Purpose of the Study:
- To address the dimensionality issue of conical intersections in TDDFT.
- To develop a new method that corrects the dimensionality of conical intersections.
- To enable more accurate simulations of photochemical reactions.
Main Methods:
- Proposing the configuration interaction-corrected Tamm-Dancoff approximation (CIC-TDA).
- Calculating the coupling between reference and response states by treating KS determinant and LR as wave functions.
- Comparing CIC-TDA results with KS-TDA for accuracy and dimensionality.
Main Results:
- CIC-TDA yields results comparable to KS-TDA away from conical intersections.
- CIC-TDA correctly reproduces the dimensionality of conical intersections (F-2).
- Formal analysis and test results validate the method's effectiveness.
Conclusions:
- CIC-TDA resolves the dimensionality problem of conical intersections in TDDFT.
- The new method enhances the applicability of TDDFT for realistic photochemical studies.
- CIC-TDA is anticipated to advance the field of computational photochemistry.
Keywords:
Kohn−ShamTamm−Dancoffconfiguration interaction-correctedlinear responsetime-dependent density functional theoryMore Related Videos
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