Atomic dynamics in liquid KxSb1−x alloys

Abstract

The atomic dynamics of liquid K x Sb 1-x alloys is studied using cold neutron inelastic scattering.Dynamical properties extracted from the experimental spectra, like the dispersions obtained from the maxima of the longitudinal current correlation function, ) ,, and the vibrational spectra, show a strong dependence on concentration. With increasing content of Sb, higher frequency modes are observed in the vibrational spectrum. For the Sb-rich compositions the dispersion is split into two branches. This indicates the de-coupling of the dynamics of the two components, due to the difference in atomic mass, already around the position of the principal peak of the static structure factor, S(Q). The observations are consistent with results from earlier experiments on similar systems and from ab initio molecular dynamics simulations.

"Non-simple liquids" - a challenge for neutron Brillouin scattering?

“…This is accompanied by the shortening of the interatomic distances observed as a shift of the dispersion minimum to larger Q, which follows the shift of the principal peak of S(Q). If the mass difference between the components is large enough, like in Na x Sn 12x [7] or K x Sb 12x [9] alloys, two dispersion branches are observed around Q p .…”

“…In a series of INS experiments, the atomic dynamics in different Zintl-type liquids, Na x Sn 12x [7], Rb x Sb 12x [8], K x Sb 12x [9], was studied. For the dynamic region around Q p , measurements were made at the cold neutron time-of-flight spectrometer IN6 at the ILL with an incident neutron energy of 4.75 meV and an energy resolution of 0.17 meV (FWHM).…”

Electronic Transport and Thermodynamic Properties of Binary Liquid Alloy: Ab Initio Approach

“…LI-BASED alloys and, hence, Zintl systems have been a matter of investigation during the past few decades [1][2][3][4][5][6][7][8][9][10] because of its immense technological importance. This class of systems is formed when the intermetallic compounds of the alkali metals are mixed with Grade IV elements, exhibiting a peculiar crystal structure associated with a variety of chemical-bond types.…”

Local atomic and electronic structures of equiatomic liquid alloy KSb from 923 to 1773K

“…For liquid KSb alloys the variation of alloy composition allows a change of the dominant type of atomic structure from metallic to ionic and to partly covalent due to charge transfer. As binary Zintl-type liquids, they are often used as model systems to study the influence of the interatomic potential on the atomic dynamics in recent years [6][7][8]. Many investigations have been done on the atomic structure of equiatomic liquid alloy KSb.…”