Systematic behaviour in trivalent lanthanide charge transfer energies

作者：Dorenbos P^*

来源：Journal of Physics: Condensed Matter , 2003, 15(49): 8417-8434.

DOI：10.1088/0953-8984/15/49/018

Information on the energy that is needed to transfer an electron from the valence band of an inorganic compound to a trivalent lanthanide impurity is presented. The energy is a measure of the location of the ground state of the divalent lanthanide relative to the top of the valence band. A variation with type of lanthanide is found that is the same irrespective of the type of compound (fluorides, chlorides, bromides, iodides, oxides, sulfides). The variation is anti-correlated with the known variation in fd transition energies in divalent lanthanides. Because of the anti-correlation, the energy difference between the first 4f(n-1) 5d state and the bottom of the conduction band is relatively invariant with type of lanthanide ion. The difference is largest for Eu(2+), and decreases gradually towards the end of the lanthanide series by 0.5 eV for Yb(2+). Based on the systematic variation in charge transfer energy and fd energy, a three-parameter model is presented to position the energy levels for each divalent lanthanide relative to valence and conduction band states. Using a similar model the levels of trivalent lanthanides are positioned.

• 出版日期2003-12-17