Lattice dynamics of YCu₂

The lattice dynamics of the orthorhombic YCu₂ compound has been studied by inelastic neutron scattering on a single crystal. An axially symmetric Born-von Karman model was applied to fit the neutron data. Ab initio calculations of the lattice dynamics at the Γ-point provided important additional information for the Born-von Karman fit procedure. The calculated phonon density of states was compared with time-of-flight experiments on powdered YCu₂ sample material. The experimental studies were completed by Raman experiments and measurements of specific heat, thermal expansion, and compressibility.