Fully Integrated Approach to Compute Vibrationally Resolved Optical Spectra: From Small Molecules to Macrosystems
Vincenzo Barone1, Julien Bloino1, Malgorzata Biczysko1
1Dipartimento di Chimica "Paolo Corradini" and CR-INSTM Village, Universita di Napoli Federico II, Complesso Univ. Monte S. Angelo, via Cintia, 80126 Napoli, Italy, and Istituto per i Processi Chimico-Fisici, Area della Ricerca-CNR, via G. Moruzzi, 56124 Pisa, Italy.
Journal of Chemical Theory and Computation
|November 27, 2015
Summary
A new method computes vibrationally resolved electronic spectra from first principles. This approach integrates with computational chemistry software for accessible theoretical spectra calculations.
Area of Science:
- Computational Chemistry
- Theoretical Spectroscopy
- Quantum Mechanics
Background:
- Accurate computation of electronic spectra is crucial for understanding molecular properties.
- Existing methods may lack generality or ease of use for vibrationally resolved spectra.
- First-principles calculations provide a robust foundation for theoretical spectroscopy.
Purpose of the Study:
- To develop and integrate a general, time-independent approach for computing vibrationally resolved electronic spectra.
- To provide a user-friendly tool within a widely used computational chemistry package (Gaussian).
- To enable the straightforward combination of Franck-Condon integral calculations with diverse electronic structure models.
Main Methods:
- Integration of a time-independent computational method into the Gaussian package.
- Utilizes geometry optimization and frequency calculations for each electronic state.
- Combines Franck-Condon integral calculations with various quantum mechanical and QM/MM models.
Main Results:
- Successful implementation of a general and effective method for theoretical spectra computation.
- Demonstrated ease of use for calculating absorption and emission spectra across the UV-Vis region.
- Applicability shown for systems ranging from small to large molecules in both gas and condensed phases.
Conclusions:
- The developed computational tool offers a straightforward and versatile approach to theoretical electronic spectra.
- The method's compatibility with various electronic structure and environmental models enhances its applicability.
- This work facilitates advanced spectroscopic studies from first principles.
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