The structure, isomerization pathways and vibrational spectra of the important heterocyclic 2-(1,2,4-triazolyl) phenol molecule were investigated by DFT calculations and matrix isolation FTIR spectroscopy. Among forty-five minima located on PES three isomers with intramolecular hydrogen bond O-H center dot center dot center dot N, 2-TRP1, 1-TRP1 and 1-TRP2, are the most stable forms with the calculated abundance of 83.4%, 10.3% and 6.0%, respectively. The presented FTIR results allow identification and characterization of these species. Several hydrogen bond parameters such as OH bond distance, vOH wavenumber shift and occupancy of the antibonding sigma*(OH) orbital were found to be linearly related with the estimated interaction energy. (C) 2016 Elsevier B. V. All rights reserved.