Crystal field in ErGa3 - a neutron spectroscopy study

The splitting of the J = 15/2 multiplet of Er3+ in a cubic crystal field ha s been determined by inelastic scattering from a polycrystalline sample of ErGa3. On the basis of the observed intensities and their temperature varia tion we have been able to determine two crystal electric field (CEF) parame ters required for cubic symmetry. Least-squares fits applied to the observe d spectra taken at various temperatures gave crystal field parameters: B-4 = (7.15 +/- 0.05) x 10(-5) and B-6 = (1.28 +/- 0.05) x 10(-6) meV yielding the Gamma (7) doublet as a ground level with the overall splitting of 10.92 meV. The results are used to calculate the temperature-dependant zero-fiel d magnetisation, the Schottky anomaly of the specific heat associated with the CEF splitting of Er3+ in ErGa3, and the high-field magnetisation. (C) 2 000 Elsevier Science B.V. All rights reserved.