Energy distribution measurements for a weak plasma-assisted emission of electrons and ions, generated at the surface Of L-a alanine doped TGS (LATGS) single crystals under driving (10(3) to 10(4) V/cm) ac electric field, have been carried out. These plasma-assisted emission processes are produced during positive charging of the emitting sample surface due to switching of the spontaneous polarization or normal charging of the dielectric sample. The energy of electrons monitored under our experimental conditions were focused at about 200 eV; contrary to the energy of electrons, the ions have broad energy spectra with energies up to a few hundreds of eV. Moreover, the influence of internal bias on the energy spectra registered for electrons is observed. (C) 2003 Elsevier B.V. All rights reserved.