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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Frequency-dependent response properties and excitation energies from one-electron density matrix functionals
Katarzyna Pernal1, Jerzy Cioslowski
1Section Theoretical Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands. pernalk@univ.szczecin.pl
Physical Chemistry Chemical Physics : PCCP
|November 16, 2007
Summary
Time-dependent density matrix functional theory (TD-DMFT) improves calculations for molecular properties. An ad hoc correction enhances accuracy, particularly at low frequencies, and resolves ambiguities in calculations.
Area of Science:
- Quantum Chemistry
- Computational Physics
Background:
- Time-dependent density matrix functional theory (TD-DMFT) is a recent advancement for calculating molecular properties.
- Accuracy is often limited by approximations and the quality of energy functionals.
Purpose of the Study:
- To assess the impact of approximations and functionals on TD-DMFT accuracy.
- To evaluate an ad hoc correction for low-frequency behavior.
- To investigate TD-DMFT's ability to resolve ambiguities in calculations.
Main Methods:
- Test calculations on small diatomic molecules.
- Analysis of frequency-dependent response properties and excitation energies.
Main Results:
- An ad hoc correction significantly improves the adiabatic approximation at low frequencies.
- TD-DMFT effectively removes ambiguity in two-electron integral selection.
- Current BBC-type functionals lack sufficient accuracy for quantitative excitation energy predictions.
Conclusions:
- TD-DMFT shows promise for accurate molecular property calculations.
- Further development of energy functionals is needed for reliable quantitative predictions.
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