| Autor: |
A. Besley, Nicholas, L. Doltsinis, Nikos |
| Zdroj: |
Journal of Chemical Theory and Computation; November 2006, Vol. 2 Issue: 6 p1598-1604, 7p |
| Abstrakt: |
A combination of Car-Parrinello molecular dynamics (CP-MD) and high-level ab initio quantum chemical calculations has been used to calculate the electronic absorption spectrum of formamide at finite temperatures. Thermally broadened spectra have been obtained by averaging over a large number of single-point multireference configuration interaction excitation energies calculated for geometries sampled from a CP-MD simulation. Electronic excitation spectra of possible contaminants ammonia and formamidic acid have also been computed. Ammonia exhibits a strong peak in the shoulder region of the experimental formamide spectrum at 6.5 eV, and formamidic acid has a strong absorption above 7.5 eV. The calculations reproduce the shape of the experimental absorption spectrum, in particular, the low-energy shoulder of the main peak, and demonstrate how finite-temperature electronic absorption spectra can be computed from first principles. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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