Vibrational spectra of the non-superconducting Ln<SUB>2</SUB>BaCuO<SUB>5</SUB> “green phases”

Abstract

In this paper we report the vibrational spectra of the so-called "green phases", of composition Ln<SUB>2</SUB>BaCuO<SUB>5</SUB>. These materials are not superconducting but often appear as a major impurity during the synthesis of the superconducting ceramics.