[en] Total cross sections for reactions in the nuclei ₄₅Sc, ^natTi, ₅₁V, and ^52,53,54Cr have been measured for 13.6-MeV deuterons and 27.2-MeV α particles. Irregularities in the behavior of the total cross sections for the reactions have been observed, which are known as the isotope-isotone effect in reaction total cross sections. Quasiclassical calculations of the total cross sections for interaction of α particles with nuclei have shown that the isotope-isotone effect can be explained on the assumption that there is a difference in the density distribution in the surface layer of nuclei for isotopes and isotones. A similar conclusion results also from analysis of experimental data on the total cross sections for interaction of both deuterons and α particles with nuclei according to the optical model. Parameters are given for optical potentials which satisfactorily describe the total reaction cross sections and the differential cross sections for elastic scattering by the investigated nuclei