Radiative lifetimes of the FeO orange system

The ground-state FeO molecules are generated from photolysis of Fe(CO)5 in a Fe(CO)5/M(O2 or N2O)/Rg(He or Ar) mixture using an unfocused weak UV laser beam. The formation of ground-state FeO molecules is identified by a laser-induced fluorescence (LIF) method. The LIF signal from FeO molecules is stronger in O2 than in N2O at the same partial pressures. The radiative lifetimes for seven bands in the FeO orange system are measured. They are substantially different depending on the excited band ranging from 260±30 ns to 590±50 ns.