The solution of Eu3+ ions in BaLiF3 is analysed through a defect simulation technique. The new relaxed positions of the nearest neighbour fluoride ions with respect to the central Eu3+ ion are used to calculate the crystal field parameters. The set of non-zero crystal field components shows that the symmetry of the central ion is CA. The Eu3+ ion dissolved in the matrix is thus generating a new site with a symmetry not usually found in the perovskite family. This explains the observed emission characteristics of the Eu3+ ion that have been recently reported. It was found that the solution energy for Eu3+ in the BaLiF3 matrix is highly positive, indicating that the substitution of the Eu3+ at the Ba2+ site has a low probability, this latter result explaining why the observed emission intensities are weak. (C) 2003 Elsevier Science B.V. All rights reserved.