Pt/NaY was prepared by the aqueous ion-exchange method and investigated by EPR spectroscopy. After reduction with H2 using a static system, an orthorhombic EPR signal was observed with g1 = 2.531, g2 = 2.322, g3 = 2.062, coaxial with the hyperfine components a1 = 64.9 G, a2 = 74.6 G, a3 = 72.6 G; this signal is assigned to Pt+ ions. Typical cation sites for location in the supercages are excluded for symmetry reasons.
