A matrix isolation infrared spectroscopic study of thermal isomerisation of 1-butanol

Highlights: • Matrix isolation infrared spectroscopy of 1-butanol. • Fourteen conformers of 1-butanol are identified on potential energy surface. • Conformer specific assignment of IR spectra. • Thermal isomerisation from TGt to TGg conformers upon thermal cycling. • Thermal isomerization happens via. quantum tunnelling. 1-butanol has fourteen distinct conformers. Vibrational spectroscopy in O-H and C-O stretching frequency region is reported earlier. Conformer specific assignment is not yet carried out. Herein, 1-butanol is investigated in the nitrogen matrix at 8 K. Eight distinct bands have been observed in the O-H stretching region and nine distinct bands have been observed in the C-O stretching region. Conformer specific assignment of the observed O-H and C-O bands is carried out. Thermal cyclisation of the deposited matrix resulted isomerisation between the two most stable conformers along with others that has been monitored using O-H and C-O bands.