39 research outputs found
Evaluation of Kubiëna’s contribution to micropedology. At the occasion of the seventieth anniversary of his book “Micropedology”
Fluorescence properties and stimulated emission in substituted europium chelates
Benzoyltrifluoroacetone was mono-substituted by F, Cl and Br in the ortho-, meta- and para-position of the benzene ring. The nine substituted ligands were used to prepare the tetrakis Eu(III) chelates. Fluorescence and absorption were studied. In general, it was found that ortho-substitution reduces the threshold energy for stimulated emission