Internal energy effects on the reaction of D3+with CH4

A tandem mass spectrometer has been used to measure the distribution of ionic products resulting from the reaction of D 3 + with CH 4 as a function of the average number of D 3 + -D 2 collisions occurring in the source. These results provide information on the amount of internal excitation energy in D 3 + . It is shown that at least 69% of the D 3 + ions are formed with 0.6 eV or more excitation energy. These results are compared with an approximate D 3 + excitation energy distribution based upon a statistical model which assumes a random distribution of energy among the vibrational and translational states of the products of the reaction of D 2 + with D 2 . Reasonable agreement was obtained.