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Surfaces of three selected materials have been investigated by means of low-energy ion-scattering (LEIS) technique: 1) the magnetite (Fe3O4) exhibiting the so-called Verwey transition (TV (bulk) = 125K) accompanied by a small cubic-monoclinic crystal distortion, 2) the intermetallic compound NdMn2 undergoing an antiferromagnetic-paramagnetic phase transition (TN = 104K) accompanied by a large crystal distortion with a volume change of 1%, and 3) the typical insulator BaTiO3 with two structural transitions below 300K. The primary energy of the (Ne+; Ar+) ion beam was in the range of 4-8 keV, and the LEIS spectra were collected in the temperature range of 85K - 300K. A large inluence from the Verwey transition on the neutralization and re-ionization of scattered ions from magnetite surface was observed, while no visible change at the magnetic phase transition in
NdMn2 realed in the LEIS spectra. A strong dependence of the characteristics of the LEIS spectra on the irradiated time was observed for BaTiO3 indicating that this surface was heavily charged by ion bombardments
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