Inelastic x-ray scattering measurements on liquid Bi were carried out. Prominent acoustic mode excitations were observed in the dynamic structure factor to beyond 12nm-1, which resolves previously conflicting results as to their presence beyond 6nm-1. We find the dispersion curve of the excitation energy with momentum transfer is nearly flat from 7 to 15nm-1 consistent with ab initio calculations of liquid Bi [J. Souto, Phys. Rev. B 81, 134201 (2010)PRBMDO1098-012110.1103/PhysRevB.81.134201]. Our ab initio and classical molecular dynamics simulations suggest that a long-range force is needed to reproduce the flatness of the dispersion curve, and the long-range force is correlated with a local structure consisting of shorter and longer bonds in the liquid.
|Physical Review B - Condensed Matter and Materials Physics
|Published - 2015 Aug 25
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics