Elucidation of the electron transfer mechanism in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow><mml:mi>Eu</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow><mml:mi>Sm</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math> codoped <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>CaF</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>: A step towards better understanding of trapping and detrapping in luminescent materials
Jonas Joos, David Van der Heggen, Lucia Amidani, Luis Seijo, Zoila Barandiarán
Abstract
Many-electron multiconfigurational ab initio calculations are combined with x-ray spectroscopy to scrutinize a popular model for electron transfer in lanthanide-doped crystals which hypothesizes that the electrons are conveyed by the conduction band of the host. Contrary to this accepted picture, our combined theoretical-experimental effort shows that the reversible electron phototransfer from ${\mathrm{Eu}}^{2+}$ to ${\mathrm{Sm}}^{3+}$ in ${\mathrm{CaF}}_{2}$ is direct, from metal to metal. It is theoretically predicted and experimentally verified that visible light induces the reverse electron transfer.
Topics & Concepts
Electron transferElectronLanthanideConduction bandPhysicsAlgorithmAtomic physicsCrystallographyChemistryPhysical chemistryComputer scienceQuantum mechanicsIonLuminescence Properties of Advanced MaterialsInorganic Fluorides and Related CompoundsAmmonia Synthesis and Nitrogen Reduction