Are Long-range Dynamical Interactions Between Screened Ions in Liquid Metals Observable in Atomic Transport and Neutron Scattering?

Abstract

Indirect static interactions between two screened ions at separation R in simple liquid metals fall off as cos 2k_fR/R ³ where a sharp Fermi sphere, radius k_f , is assumed. Recently it has been proposed that long-range dynamic interactions exist, of asymptotic form cos 2k_fR/R ².

Pure isotope measurements on light liquid metals offer a possible means of observing such effects, though order of magnitude estimates of the effects seem presently difficult. However, fairly strong electron-ion interaction, plus large isotopic mass difference, are clearly needed. Li⁶ and Li⁷ are therefore favourable. The shear viscosities of these isotopes have been measured and seem to support the present ideas at least qualitatively.