Abstract. Absolute net nuclear polarizations and their time and concentration dependences are reported for the products of laser pulse initiated electron transfer from naphthalene and naphthalene derivatives to 1,2-dicyanoethenes. They represent different prototype cases for radical ion pair formation and decay pathways and are used to test predictions from the highfield radical pair theory of CIDNP. By quantitative analyses reaction efficiencies, rate constants for degenerate electron exchange and nuclear relaxation times of the radical ions are obtained.