In previous articles, the propanal FIR spectra have been studied theoretically using ab initio calculations and they have been compared with experimental results reported in the literature. In the present work, the zero point vibrational energy correction to the energy (ZPVE) is introduced to calculate the simultaneous asymmetric aldehydic and methyl torsion spectra for the propanal deuterated species, for which observed spectra are known. In the case of the aldehydic torsion, the ZPEV correction is essential to reproduce the experimental data. Thus, the fundamentals for the studied species have been found to be close to the corresponding experimental data. (c) 2007 Elsevier B.V. All rights reserved.