Polarized Absorption and Emission in an Octacoordinate Chelate of Eu3+

Abstract

Polarized absorption in the 5D2←7F0 transition and emission in the 5D0→7F2 transition of the Eu3+ ion have been obtained in monoclinic single crystals of the tetrahexylammonium salt of tetrakis diphenyl-propanedionoeuropium (III). Both sets of transitions consist of three lines, two polarizing strongly perpendicular to the crystallographic c axis, the third polarizing parallel to this axis. Assuming the propriety of electric-dipole selection rules, these results are consistent with S4 symmetry for the chelate anion.