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Updated: Jul 4, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Rotationally resolved electronic spectroscopy of water clusters of 7-azaindole
Thi Bao Chau Vu1, Ivo Kalkman, W Leo Meerts
1Institut für Physikalische Chemie I, Heinrich-Heine-Universität, D-40225 Düsseldorf, Germany.
Abstract:
The rotationally resolved electronic spectra of the electronic origin of the 7-azaindole-(H(2)O)(1) and of the 7-azaindole-(H(2)O)(2) clusters have been measured in a molecular beam. From the rotational constants the structures in the S(0) and S(1) electronic states were determined as cyclic with the pyrrolo NH and the pyridino N atoms being bridged by one and two water molecules, respectively. Excited state lifetimes of about 10 ns for both clusters have been found. In the spectrum of the 7-azaindole-(H(2)O)(2) cluster a splitting of the rovibronic band is observed, which can be traced back to a large amplitude motion, involving the out-of-plane hydrogen atoms of the water chain. Both the changes of the rotational constants upon electronic excitation and the orientation of the transition dipole point to a solvent induced state reversal between the L(a) and the L(b) states upon microsolvation.
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