| Autor: |
Ishii, Takugo |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 1/8/2005, Vol. 122 Issue 2, p024705, 6p, 2 Diagrams, 1 Chart, 3 Graphs |
| Abstrakt: |
A first-principles multielectron method is applied to the calculations for the cooperative transitions of trivalent ytterbium ions (Yb3+) in yttrium aluminum garnet (Y3Al5O12; YAG) and yttrium sesquioxide (Y2O3) crystals. The method is based on a molecular-orbital method, in which the overlap between the Yb 4f and the oxygen 2p orbitals is directly considered through a self-consistent procedure. A Yb23+ two-ion model and a (Yb2O14)22- dimer cluster embedded in the point charges of the YAG lattice are compared. The 4f-2p overlaps in the cluster model is needed to explain the cooperative transition probability originating from electric dipole transitions. A (Yb2O10)14- dimer molecule in Y2O3 lattice produces larger electric dipole transition probabilities than the case of YAG. The smaller coordination number in Y2O3 produces the larger 4f-2p overlaps, which result in the larger transition probabilities. © 2005 American Institute of Physics. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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