Elucidation of site-selective doping in heteropolynuclear lanthanide cluster aggregates

Lanthanide upconversion (UC) converts two low energy photons into emission of a single high-energy photon - for example using Yb donors and a Tb acceptor - which has applications in new types of medical imaging and energy harvesting. One crucial aspect of UC involves the ion-ion distances and distribution, which governs the efficacy of the energy transfer step. The use of single-crystal neutron diffraction will allow determination of the site-selective doping which occurs in heteropolynuclear clusters, which will permit mathemetical modelling and interogation of the mechanism in this poorly understood phenomenon.