Feshbach states of the propadienylidene anion H2CCC−
Abstract
The 2A″,
2A1
and
2B1←
2B1 electronic transitions by means of ab initio calculations. The autodetachment rate increases with energy. A comparison of the laboratory data with diffuse interstellar bands shows that not only the four strong transitions of the Ã
2A1←
2B1
system
but also several of the Feshbach resonances lie close to astronomical absorptions.