Effects of Possible Spin-Spin Interactions on EPR spectra of Cu2+ exchanged Faujasite–X (I)

Abstract

The interpretation of the continuous wave electron paramagnetic resonance (CW-EPR) spectra of Cu2+ exchanged in Faujasite zeolite is not straightforward. Recent literature points to the role of both Cu2+ zeolite sites and Cu2+ relationship to lattice Al in determining the parameters of Cu2+ spin Hamiltonian. Our work shows that at low concentration, Cu2+ EPR signals show negligible spin-spin interactions. At higher Cu (II) concentrations, a third CW-EPR spectrum that has contributions from both the CW-EPR and the spin-spin interactions, appears.