The mixing of the 4f2 1S0 state with the 4f5d states in Pr3+ doped SrAl12O19

The 1S0 state of Pr3+ in SrAl12O19 lies near to the 4f5d band. The admixing of the opposite parity 5d components by the crystal field without a symmetry center can be significant, thus affecting the properties of the 1S0 state. In a crystal with D3h symmetry, the major 4f5d components which can be mixed into 1S0 are 2−1/2(|fdΓ1 1F3 3〉-|fdΓ1 1F3-3〉) and 2−1/2(|fdΓ1 1H5 3〉-|fdΓ1 1H5-3〉). A calculation of the 4f5d wavefunctions indicates that the states which may be mixed into 1S0 lie mainly at the middle and upper parts of the 4f5d configuration. The mixed 4f2 1S0 wavefunction is then calculated and its spectral properties are discussed.