Chemical Composition of and Eu2+ Luminescence in the Barium Hexaaluminates

Abstract

This paper consists of two parts. In the first part the chemical composition of two kinds of barium hexaaluminate (one poor and one rich in barium) is explained using the local electroneutrality concept. In the second part a reinvestigation of the Eu2+ luminescence in these compounds is reported. The emission spectrum of each of the two compounds shows two emission bands: a blue and a green emission band, indicating the presence of two Eu2+ sites. The blue emission band is ascribed to Eu2+ ions at barium sites, whereas the green emission band is identified with Eu2+ ions incorporated at aluminum sites within spinel blocks of the structure.