In charge inversion experiments using a tandem mass spectrometer, mass-selected positive ions are made to collide with an alkali metal target, and the resulting negative ions formed upon two-electron transfer are mass-analyzed. The internal energy depositions are measured for the so-called thermometer molecule W(CO)(6). The difference between the centered value of the internal energy of W(CO)(6) and the energy level of the precursor ion is in good agreement with the ionization energy of the Cs target. This correlation indicates that dissociation occurs from energy-selected neutrals formed via near-resonant neutralization.