LOW-ENERGY-ELECTRON TRANSPORT IN ALKALI-HALIDES

A model of electron transport in alkali halides, below 10 eV, is descr ibed. It is based on theoretically calculated microscopic cross sectio ns of electron interactions with lattice phonons. Both acoustic and op tical scatterings are taken into account, the former being also treate d as a quasielastic process that randomizes the electron motion. Monte Carlo calculations based on the model simulate the UV-induced photoel ectron emission from CsI. The calculated quantum efficiency and energy spectra are in good agreement with experimental data, in the photon e nergy range of 6.3-8.6 eV. The probability for an electron to escape f rom CsI, NaCl, and KCl is provided as a function of its energy and cre ation depth. A comparison is made between our approach and other pheno menological models.