Orbitally ordered Jahn-Teller state

Fig. 8 Upper panel schematic representation of fulleride ion orientation in various Jahn-Teller states. The arrow indicates the crystallographic c-axis, the bars in the ovals the orientation of a hexagon-hexagon double bond. Lower panel The split frontier MOs of the ions and the dipole allowed transitions indicated by arrows. For comparison we depicted these MOs for the Ih Ceo, as well. The ordering of the b -2,u and of the b - g orbitals is arbitrary. [4] Copyright (2006) by the American Physical Society...

The second order Jahn-Teller effect couples electronic states which arise from different electron configurations. Because the symmetry species of the states f j) and l y) are determined by the symmetry of the orbitals which are occupied, the... 

Vibrational stmcture is, at best, only partially resolved. The stmcture in the first and second systems is complex which could be due, in part, to there being a Jahn-Teller effect in each of them. Such an effect may arise when a molecule is in an orbitally degenerate E (or T) state. The Jahn-Teller effect involves a distortion of the molecule in order to destroy the... 

Oddershede s calculations were limited by the computational facilities and more recent calculations indicate that while Manne s ordering of the occupied molecular orbitals stays unchallenged, there is little significance to assign to virtual orbitals for an anion [6]. It was pointed out [5] that ionization from a degenerate state would lead to a distortion in the system due to the Jahn-Teller theorem. 

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