Isotope effects on the Raman spectra of CuCl

✍ Scribed by A. Göbel; T. Ruf; M. Cardona; C.T. Lin

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 203 KB
• Volume: 219-220
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(95)00795-4

✦ Synopsis

We report on changes of the LO and TO Raman phonons of CuCl with isotopic substitution of copper (63Cu, 65Cu).

While the LO phonon peak shifts according to changes of the reduced ion mass, isotope effects on the frequencies of peaks belonging to the anomalous TO phonon structure are much larger, actually close to those expected for the Cu masses. We attribute this paradoxical result to a strong anharmonic interaction of the TO phonon with an LA/TA combination band reflecting different isotope effects on optic and acoustic modes interacting via a Fermi resonance.