title: Homogeneity of doping with paramagnetic ions by NMR.
abstract: In NMR, paramagnetic dopants change the relaxation behavior and the chemical shift of the nuclei in their immediate environment. Based on the concept that the "immediate environment" in a diamagnetic host material can be described as a sphere with radius r0, we developed a function for the fraction of unperturbed nuclei (the fraction of nuclei outside the sphere) which gives a link between the effective radius and the doping concentration. In the case of a homogeneous doping scenario a characteristic dependence is observed in both theory and experiment. We validated the model on a sample series where paramagnetic Eu(II) ions are doped into crystalline SrH2. The fraction of unperturbed nuclei was determined from the (1)H NMR signal and follows the predicted curve for a homogeneous doping scenario where the radius r0 is 17 Å.
authors.affiliation: Inorganic Materials Chemistry, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany. schmedt_auf_der_guenne@chemie.uni-siegen.de.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Li
authors.forename: Vinicius R
authors.initials: VR
authors.lastname: Celinski
authors.forename: Johannes
authors.initials: J
authors.lastname: Weber
authors.forename: Nathalie
authors.initials: N
authors.lastname: Kunkel
authors.forename: Holger
authors.initials: H
authors.lastname: Kohlmann
authors.forename: Jörn
authors.initials: J
authors.lastname: Schmedt auf der Günne