Evaporation after ionization in clusters has been studied in the 1-naphthol–(NH₃)_n case. From this study, it appears that, for n3, all clusters evaporate at least one ammonia molecule in the excitation and/or ionization processes. This leads to the conclusion that the ground state proton transfer occurs in clusters with n6, and if there is an excited state proton transfer, it occurs only at n = 5.