It is shown by use of Fourier transform ion cyclotron resonance (FTICR) mas
s spectrometry that photoexcitation of protonated naphthalene by visible la
ser light of 488 nm can effect a proton transfer from this ion to acetonitr
ile. The reaction of the ground state reaction partners is endoergic by 31
kJ/mol. (C) 1999 Elsevier Science B.V.