CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Electronic transition moments of 2-aminopurine

Anders Holmén (Institutionen för fysikalisk kemi) ; Bengt Nordén (Institutionen för fysikalisk kemi) ; Bo Albinsson (Institutionen för fysikalisk kemi)
Journal of the American Chemical Society (0002-7863). Vol. 119 (1997), 13, p. 3114-3121.
[Artikel, refereegranskad vetenskaplig]

The electronic spectrum of the unnatural nucleic acid base 2-aminopurine is important in order to understand the spectroscopy and photophysics of the normal DNA bases. Knowledge of transition moment directions and effective absorption components is also a prerequisite for the interpretation of emission spectra of 2-aminopurine incorporated into DNA as a probe of nucleic acid base motion or excitation energy transfer processes. Using linear dichroism, fluorescence anisotropy, and ordinary and magnetic circular dichroism techniques, the near-UV spectrum of 2-aminopurine is resolved into contributions from five electronic transitions. Four moderately strong pi-->pi* transitions (I, III, IV, and V) are observed, polarized at +53 degrees (I), -72 degrees (III), -77 degrees (IV), and +57 degrees or -67 degrees (V) relative to the short molecular axis. In addition, one weak n --> pi* transition (II) polarized perpendicular to the molecular plane has been identified. Semiempirical INDO/S calculations support these assignments.

Nyckelord: differential-overlap technique, linear dichroism measurements, magnetic, circular-dichroism, stretched polymer sheets, intermediate neglect, polarization spectra, metal complexes, excited-states, base pair, eco-ri



Denna post skapades 2011-07-14.
CPL Pubid: 143447

 

Läs direkt!


Länk till annan sajt (kan kräva inloggning)


Institutioner (Chalmers)

Institutionen för fysikalisk kemi (1900-2003)

Ämnesområden

Kemi

Chalmers infrastruktur