Adenine, calculated spectra

Fig. 10.31 Observed (top) and calculated (bottom) INS spectrum of alanine dipeptide in the 0-500 cm" region. In the calculated spectrum methyl group contributions are shown N-methyl, dotted line terminal, dashed line side-chain, thin solid line.. Reproduced from [76] with permission fi"om Adenine Press.

In Figure 31, we compare the associated spectrum of the fast component in 9-methyl adenine with calculated [194] Franck-Condon structures for the 7i7t —> Dq(n 1) +e (solid line) and 7171 —> Diin 1) + e (dash-dotted line) ionizing transitions. The two separated peaks agree well with the FC calculations, strongly suggesting that the short-lived state in 9-methyl adenine is the 7i7t state. By contrast, adenine contains an additional contribution that... 

Fig. 4 IR-UV double resonance speclnun of adenine with the R2PI laser tuned to (a) 36,105 cm and (b) 35,824 cm. The stick spectrum shows the vibrational frequencies calculated at the B3LYP/ 6-311G(d,p) level. Data from PlUtzer and Kleinermanns (reprinted with permission, color coding added) [42]. Stick speara were computed at the B3LYP/6-31G(d) level with a scaling factor of 0.9613...

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