The pulsed laser desorption of monoatomic Al and Na ions was studied at 266 nm with the mass spectrometric time-of-flight (TOF) method at laser fluences between 60 and 85 mJ cm(-1). This range is below the laser ablation threshold, and fragmentation of the zeolite framework has not been observed. Near the desorption threshold (similar to 60 mJ cm(-1)) the kinetic energy (KE) distribution of the translating Al species fits a Gaussian profile, which can be interpreted on the basis of a photochemical model with surface relaxation processes taken into account. Laser desorption of Na species induced the pink-colored center associated with Na clusters. It is proposed that the Na clusters are formed by migration and should be less reactive to laser desorption than other laser-desorbed Na species in zeolites. As laser fluence increased, the KEs of laser-desorbed Al and Na species had shifted Maxwell-Boltzmann (SMB) distributions, which are due to thermalization of the species in flux by collision. Ionic and neutral species are observed in the collisional flux when the KE at TOF peak maximum (KE(p)) is above and below the ionization potential of the desorbed species, respectively. KEs of translating ionic species (> 6.6 eV) are higher than the 266 nm photon energy (4.66 eV), which is explained by a multiphoton excitation process. The origin of laser-desorbed Al species is considered. It is suggested that the 266 nm laser TOF method may be very sensitive to the mobile Na and Al species in zeolites.