Theoretical study of the molecular structure of TATFIW

The molecular structure of triacetyltriformylhexaazaisowurtzitane (TATFIW) was optimized and its IR harmonic frequency was calculated by Gaussian 98 software package at the level of B3LYP/6-31G. It was found that molecular inner hydrogen bond exists in TATFIW, acetyl is easier off than formyl in the nitrolysis with nitric-sulfuric mixed acid, by analyzing bond length, bond angle, dihedral angle and charge of TATFIW theoretically. Above mentioned result agrees well with that of the experiment. The comparison of IR harmonic frequency and intensity between calculated and experimental values, the relative error of IR harmonic frequencies which is less than 3.6%, were given.