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Holstein-Peirls-Hubbard trimer as a model for quadrupolar two-photon absorbing dyes
Robertino Pilot1, Renato Bozio
1Consorzio INSTM, UdR Padova, Department of Chemical Sciences, Via Marzolo 1, 35131 Padua, Italy. roberto.pilot@unipd.it
Physical Chemistry Chemical Physics : PCCP
|November 18, 2010
Summary
This study explores the optical properties of Donor-Acceptor-Donor systems using a novel model. Electron-phonon coupling significantly impacts nonlinear optical phenomena like two-photon absorption.
Area of Science:
- Theoretical Chemistry
- Condensed Matter Physics
- Materials Science
Background:
- Understanding the optical properties of organic molecules is crucial for developing new electronic and photonic materials.
- Donor-Acceptor-Donor (D-A-D) systems are of interest due to their tunable electronic and optical characteristics.
- Electron correlation and electron-phonon coupling play significant roles in determining these properties.
Purpose of the Study:
- To investigate the linear and nonlinear optical properties of a D-A-D system.
- To incorporate electron correlation effects using a bi-electronic density matrix.
- To study the influence of electron-phonon coupling on optical properties.
Main Methods:
- Utilized a two-electron three-point-site model system.
- Employed a modified Collective Electronic Oscillators (CEO) method.
- Included electron-phonon coupling and considered singly- and doubly-excited states.
Main Results:
- Computed polarizabilities and second hyperpolarizabilities.
- Analyzed the impact of electron-phonon coupling on optical properties.
- Discussed effects on two-photon absorption and third harmonic generation.
Conclusions:
- The developed model effectively captures electron correlation and electron-phonon coupling effects.
- Electron-phonon coupling significantly influences nonlinear optical responses in D-A-D systems.
- Findings provide insights for designing materials with tailored optical functionalities.
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