An accurate quartic force field, fundamental frequencies, and binding energy for the high energy density material TdN4

The CCSD(T) method has been used to compute a highly accurate quartic force field and fundamental frequencies for all 14N and 15N isotopomers of the high energy density material TdN4. The computed fundamental frequencies show beyond doubt that the bands observed in a matrix isolation experiment by Radziszewski and coworkers [Chem. Phys. Lett. 328 (2000) 227] are not due to different isotopomers of TdN4. The most sophisticated thermochemical calculations to date yield a 2N2→N4 heat of reaction of 182.22±0.5 kcal/mol at 0 K (180.64±0.5 at 298 K). It is hoped that the data reported herein will aid in the ultimate detection of TdN4.