The 5f1 -> 6d1 luminescence spectrum of U4+ in CsGeF crystals. A quantum chemical study.
Résumé
The 5f^1 6d^1 (t2g)^1 emission spectrum of Cs2GeF6:U single crystals has been calculated using the relativistic ab initio model potential (AIMP) embedded cluster method. It consists of a series of broad, intense bands in the UV followed by broad and increasingly weaker bands in the visible and near infrared spectral range, which appear to be associated with emissions from the lowest 5f^1 6d(t2g)^1 excited state, 1Eu , to a number of levels of the 5f 2 manifold. The electric dipole allowed emission of highest energy, 1Eu -> 1T1g , is found to have very low oscillator strength,