Rio, CarolinaBrandão, J.Wang, Wenli2015-06-302015-06-302015-062332-3019AUT: CRI01087; WWA01535;http://hdl.handle.net/10400.1/6661The O + H2 reaction is a particular example to alert the importance of a clear definition of the quantum state of an atom when referring to a chemical reaction. In its ground state, O (3P), the oxygen atom reacts with H2 through an energy barrier with small rate constant. In contrast, when the oxygen atom is in its first excited state, O (1D), the reaction O + H2 occurs without energy barrier and the rate constant is seven orders of magnitude higher. The dynamic behaviour of this reaction depends also on the quantum state of the oxygen atom.engAtomic quantum statesChemical kinetics and reaction dynamicsRate Constantjournal articlehttp://dx.doi.org/10.13189/ujc.2015.030205