Electronic structure and thermal decomposition of 5-aminotetrazole studied by UV photoelectron spectroscopy and theoretical calculations

► Electronic structure of 5ATZ studied by photoelectron spectroscopy. ► Gas-phase 5-ATZ exists mainly as the 2H-tautomer. ► Thermal decomposition of 5ATZ gives N2, NH2CN, HN3 and HCN, at 245 °C. ► HCN can be originated from a carbene intermediate.