Trimethylenemethane, degenerate orbitals

Furthermore, we deal with a stfuctural distortion of the trimethylenemethane radical cation (TMM+) [63], The neutfal TMM has a high symmetry of and is in a triplet state with a doubly degenerate c" HOMO in the ground electronic state [64], The Z)3h structure of TMM is expected to be distorted to a Civ structure with a lower symmetry in TMM+ due to the J-T effect, so as to split the original degenerate e" orbitals into ai and b orbitals. 

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