Table 2.
Unscaled B3LYP harmonic frequencies (in cm−1) and intensities (in parentheses, in km mol−1) for the carbonyl stretching modes in thymine and thymidine
| Singlet ground state | Lowest triplet state | ||||
|---|---|---|---|---|---|
| Molecule | Basis set | ||||
| C2=O | C4=O | C2=O | C4=O | ||
| thymine | aug-cc-pVDZ | 1786 (772) | 1741 (629) | 1759 (518) | 1611 (139) |
| thymine-d2a | aug-cc-pVDZ | 1771 (604) | 1730 (784) | 1740 (491) | 1597 (139) |
| thymine | aug-cc-pVTZ | 1788 (748) | 1744 (633) | ||
| thymine-d2a | aug-cc-pVTZ | 1775 (578) | 1732 (795) | ||
| thymine | 6-311++G** | 1798 (811) | 1751 (652) | 1771 (561) | 1619 (167) |
| thymine-d2a | 6-311++G** | 1784 (634) | 1751 (820) | 1754 (531) | 1604 (183) |
| thymidine | 6-311++G** | 1771 (613) | 1749 (783) | 1753 (470) | 1633 (231) |
| thymidine-d3b | 6-311++G** | 1767 (452) | 1736 (953) | 1745 (447) | 1619 (255) |
a
Isotopomer deuterated at the N1 and N3 hydrogens
b
Isotopomer deuterated at the N3 hydrogen and both hydroxyl groups of the ribosyl moiety