Acetylene configuration, ground-state

The excited states of the enediyne moiety were approximated by a weakly interacting ethylene acetylene model where the various states are expressed as linear combinations of the configurations for one ethylene and two acetylenes. The authors examined the first six excited states of 80, three triplets and three singlets. AH methods examined predicted that the spectroscopically forbidden triplet states (DBj, DBj, and DAj, respectively) He between the singlet ground state (S ) and the first singlet excited state (I Bj). 

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