Solvent-Induced Shifts in Electronic Spectra of Uracil
| Title | Solvent-Induced Shifts in Electronic Spectra of Uracil |
| Publication Type | Journal Article |
| Year of Publication | 2011 |
| Authors | DeFusco A, Ivanic J, Schmidt MW, Gordon MS |
| Journal Title | Journal of Physical Chemistry A |
| Volume | 115 |
| Pages | 4574-4582 |
| Date Published | 05/12 |
| Type of Article | Article |
| ISBN Number | 1089-5639 |
| Accession Number | ISI:000290126900002 |
| Keywords | AQUEOUS-SOLUTION, configuration-interaction, conical intersections, distributed, excited-state dynamics, fragment potential method, initio molecular-dynamics, multipole analysis, nucleic-acid bases, perturbation-theory, reaction field-theory |
| Abstract | Highly accurate excitation spectra are predicted for the low-lying n-pi* and pi-pi* states of uracil for both the gas phase and in water employing the complete active space self-consistent field (CASSCF) and multiconfigurational quaside-generate perturbation theory (MCQDPT) methods. Implementation of the effective fragment potential (EFP) solvent method with CASSCF and MCQDPT enables the prediction of highly accurate solvated spectra, along with a direct interpretation of solvent shifts in terms of intermolecular interactions between solvent and solute. Solvent shifts of the n-pi* and pi-pi* ye excited states arise mainly from a change in the electrostatic interaction between solvent and solute upon photoexcitation. Polarization (induction) interactions contribute about 0.1 eV to the solvent-shifted excitation. The blue shift of the n-pi* state is found to be 0.43 eV and the red shift of the pi-pi* state is found to be -0.26 eV. Furthermore, the spectra show that in solution the pi-pi* state is 0.4 eV lower in energy than the n-pi* state. |
| URL | <Go to ISI>://000290126900002 |
| DOI | 10.1021/jp112230f |
| Alternate Journal | J. Phys. Chem. A |
