Synchrotron-based Fourier transform spectra of the ν23 and ν24 IR bands of hexamethylenetetramine C6N4H12

Hexamethylenetetramine (HMT), C6N4H12 is a spherical top with nine IR-active modes. Because of its relevance for astrophysics, we recorded the absorption spectra in the full range of its fundamental bands. In total, we detected eight fundamental bands and recently published the rotational analysis of the four most intense bands (nu(19), nu(20), nu(21), nu(22)) located in the 1000-1500 cm(-1) range as a support for astronomical searches (Pirali et al., 2014). While the CH stretch modes are unresolved broad features, in this article we report the analysis of the two remaining fundamental bands exhibiting rotationally resolved structures: nu(23)-GS and nu(24)-GS located at about 820 cm(-1) and 670 cm(-1), respectively. (C) 2015 Elsevier Inc. All rights reserved.