Electronic structures of the JP-10 exo-TCD stereoisomer pair exo-TCD-chair and exo-TCDboat are studied in isolation (gas phase). Briefly, the geometry optimisations were carried out using DFT-based B3LYP functional with Dunning's triple valence zeta cc-pVTZ basis set. We calculated the relaxed potential energy trajectory from the exo-TCD-chair to the exo-TCDboat through rotation of the dihedral angle controlling the triangle C8C10C9 (see Figure ).