Although attempts to measure spectra of NO2+ Using ion beam spectroscopy have been unsuccessful to date we show that the Newcastle ion-beam/infrared laser beam spectrometer should be capable of recording the spectrum calculated here. We report ab initio calculations of infrared spectra of NO2+ between levels of the A 2 H electronic state. The accuracy of our potential energy function is established by using it to synthesize a previously recorded TPEsCO spectrum of NO2+. (C) 2003 Elsevier Science B.V. All rights reserved.