 The hydration state of the first coordination sphere of manganese complexes with hydroxyethylideen diphosphonic acid, HEDP, and for MN2, systems with salt compositions of amino methylated calyx, FORF, resorcinol, AMC, a varying lipophilicity were investigated using nuclear magnetic resonance, NMR. In acidic environments, pH 2 to 4, the presence of HEDP caused a bell-shaped increase in the relaxation efficiency of MN2 complexes with AMC containing pental radicals. However, this effect was not seen when the AMC had other types of alkyl chains. This article was authored by E. A. Burilova, L. I. Vagapova, Z. A. Nazarova, and others.