Crystal Field Effect of Eu³⁺ Ion in Solid

In this paper, the influence of crystal field for Eu³⁺ ion was analysed, the difference between the free ion and the ion embedded in solid was discussed. The results show that the variation of Slater integral is relative to the structure and composition of various hosts. For calculating Slater integral, first we calculate the energy level shifts caused by J-mixing effect, then they were deduced from the experimental energy levels to obtain the real energy level values in free ion state. We utilize them to fit the Slater integral. According to calcuating results, we can obtain that 1). The value of F₂ is relative to the host, for the series of isomorphic compound, which decreases with the decrease or radius of cation. 2). The value of F₂ is relative to the number of coordination, in general, it increases with the increase of the number of coordination. 3). The main reason influencing Slater integral is the zero crystal field term.