Photon controlled electron juggling between lanthanides in compounds

The energy for electron transfer between a lanthanide dopant and the valence and conduction band of its hosting inorganic compound provides essential information on the position of lanthanide acceptor and lanthanide donor states within the band gap. The many different types of transfer are reviewed, and it is illustrated how they can be utilized to create 4f-electron binding energy schemes of the electrons in any of the 4fn states of each divalent and each trivalent lanthanide in a compound. When both an electron acceptor and electron donor lanthanide are present in the same compound electrons can be transferred between them in a controlled fashion by photon manipulation or by heat. Such electron juggling will be demonstrated in double lanthanide doped in YPO4 and Y3Al5O12.