Laser spectroscopy and hole burning of europium laurate and europium-doped lanthanum laurate

Laser spectroscopy and hole-burning measurements have been made on samples of europium laurate and europium-doped lanthanum laurate. The lanthanide laurate soaps are lanthanide salts of long chain (C-12), saturated fatty acids in which 2D layers of hydrocarbon chains arise, forming either lamellar crystals or smetic liquid crystals depending on their thermal history. In this study, solid samples of metastable liquid crystals were prepared by different cooling rates which resulted in a variation of the local disorder about the europium ions. Two symmetrically distinct europium sites have been identified within slowly cooled europium laurate. (C) 1999 Published by Elsevier Science B.V. All rights reserved.