Gas phase electronic spectrum of C3H in the visible

The electronic spectrum of C3H has been observed by means of a resonant two color two photon ionization technique sampling a supersonic plasma source. On the basis of ab initio calculations, vibrational and rotational analysi s, the complex vibronic system observed in the visible and near UV is assig ned to three electronic transitions, (A) over tilde (2)A(')<--X (2)Pi, (B) over tilde (2)A " <--X (2)Pi and (C) over tilde (2)A " <--X (2)Pi of C3H. P otential curves along the CCH bending coordinate have been obtained because of its role for the electronic spectrum and dynamics of C3H. (C) 2001 Amer ican Institute of Physics.