IR vibrational assignments for TATB from the density functional B3LYP/6-31G(d) method

Vibrational IR spectra for the 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) have been calculated at density functional B3LYP level using the 6-31G(d) basis set. The effects of isotopic species to the spectra are discussed. The characteristic band at 3322.5 and 3220.9 cmK1 is interpreted as the asymmetrical and symmetrical N–H stretching band, respectively. The band at 1571.3 and 1235.6 cmK1 is attributed to the asymmetrical and symmetrical N–O stretching band, respectively. The bands at 1613.1 and 779.56 cmK1 are attributed to the C–N stretch for the amino groups. The band at 1321.5 cmK1 is attributed to the C–N0 stretch for the nitro groups. Three bands at 1448.4, 1181.2, and 1031.4 cmK1 are assigned to the skeletal stretching modes of the aromatic ring. Three predicted very weak bands at 932.54, 539.32, and 741.48 cmK1 are found without counterparts in the experimental spectrum. q 2005 Elsevier B.V. All rights reserved.