Mössbauer Measurements in Europium-Calcium and Europium-Strontium Alloys

Abstract

Mössbauer effect measurements have been performed for Eu_xCa_1−x and Eu_xCa_1−x (0≤x≤1) alloys using the 22‐keV γ‐line in ¹⁵¹Eu. The hyperfine (hf) fields extrapolated to zero europium content are −110 kOe for the EuCa system and −140 kOe for the CuSr system as compared to −150 kOe for the EuBa and EuYb system. On the other hand the charge density at the Eu nucleus decreases only slightly in going from the EuYb to the EuCa system. The explanation of these hf‐field measurements as well as g‐shift measurements requires a varying d‐electron contribution to the conduction band.