The results of a Mössbauer spectroscopy study of several trivalent europium chelates are reported. Positive isomer shifts, relative to europium trifluoride, were observed for all of the chelates studied. These shifts are attributed to partial covalency in the europium-ligand bonds. Participation by europium 6s, 5d and 4f orbitals in this covalency is discussed in relation to the measured isomer shifts and symmetry requirements. Relatively narrow line widths and low resonance effects were observed for all of the chelates. © 1974.
Zaheer, A. H., Liss, I. B., Keck, N. B., Bos, W. G., & Ouseph, P. J. (1974). Mössbauer studies of europium chelates. Journal of Inorganic and Nuclear Chemistry, 36(11), 2515–2520. https://doi.org/10.1016/0022-1902(74)80463-X