Parthiban, S and Raghunandan, BN and Sumathi, R (1996) Structures, energies and vibrational frequencies of dinitrogen pentoxide. In: Journal of Molecular Structure (Theochem), 367 . pp. 111-118.
Several conformers have been considered for dinitrogen pentoxide $(N_20_5)$ and ab initio calculations have been performed on these conformers. Three minimum-energy structures have been identified from them viz., planar, perpendicular and fully optimized structure. The global minimum was characterized by vibrational frequency analysis. The calculations suggest that the fully optimized structure has a $C_2$ symmetry with its nitro groups rotated $\approx 35^o$ of the central N-O-N plane in a conrotatory manner. Normal mode analysis and calculation of vibrational frequencies were performed using ab initio derived force fields at the correlation level for the $6-31G^\ast$ basis set. The calculated frequencies of $N_20_5$ are discussed in comparison to those determined from experiment and density functional study.