Low-energy thermal excitations in the V-O system

Abstract

The thermal excitations of the atoms of the V-O solid solution have been investigated by the slow-neutron scattering method for low-energy transfers. The features of the low-frequency excitations of a light impurity in the metal lattice for energy transfers ɛ ≈ 1.3 and 2.4 meV have been revealed. It is assumed that the observed low-energy excitations appear in V-O due to strong local distortions around an impurity atom, which are responsible for the formation of the effective potential of a complex shape with the almost flat bottom. Analysis of the interaction of oxygen with the nearest matrix atoms shows that the low-energy excitations of oxygen atoms can be attributed to the splitting of the ground state in the complex potential. The level scheme of the split state can be obtained in the representation of decelerated circular quantum rotation about the axis passing through the two nearest metal atoms or the motion in a two-dimensional potential well. The results indicate that rotational low-energy excitations can exist in (metal-interstitial impurity) solid solutions.