Crystallization behavior of fluorozirconate glasses as monitored by 35Cl NMR

The ³⁵Cl nuclear magnetic resonance (NMR) spectroscopy was first used to study the crystallization of erbium-doped fluorochlorozirconate glass in the ZrF₄–BaF₂–BaCl₂–LaF₃–AlF₃–NaF system. It has been shown that crystallization results in the increasing homogeneity of electronic structure on chlorine atoms and a narrowing of the NMR line. The glass being crystallized, erbium cations are displaced into the fluoride phase.