Analysis of dispersion of long-wavelength optical phonons in zinc with the help of light scattering

The temperature dependences (5-300 K) of the Raman spectra of E-2g phonons and optical constants in zinc single crystals are measured in the excitation energy range 1.4-2.54 eV. It is found that phonon damping decreases upon an increase in the wavelength of exciting radiation. The obtained results arc compared with the dependence of the phonon width on the excitation energy (the probed wave vector of the excitations under investigation), which are presented for the first time for the transition metal osmium, as well as with the calculated electron-phonon renormalization of damping, taking into account the actual distribution of wave vectors. (C) 2001 MAIK Nauka/Interperiodica.