Calculated Relative Stabilities of C84

Abstract C84 is treated as a system composed of 24 local minima whose energies, geometries, and vibrational frequencies are obtained from MNDO calculations. The predicted global minimum of D2d symmetry remains the most abundant species in the equilibrium isomeric mixture only till 276 K, being replaced by a D2 species beyond that point. However, a C 1 structure is prevalent in the high temperature limit. The calculated composition around a temperature of 1000 K is consistent with very recent NMR observations.