In March 1962, Neil Bartlett, then at the University of British Columbia, observed the reaction of a noble gas. First , he prepared a red compound which is formulated as O 2+ PtF 6– . He , then realised that the first ionisation enthalpy of molecular oxygen (1175 kJ mol –1 ) was almost identical with that xenon (1170 kJ mol –1 ). He made efforts to prepare same type of compound with Xe + PtF 6 – by mixing Pt F 6 and Xenon. After this discovery, a number of xenon compounds mainly with most electronegative elements like fluorine and oxygen, have been synthesised.