Ivan Sukuba

Spin filter properties of armchair graphene nanoribbons with substitutional Fe atoms

ABSTRACT The spin filter capability of a (0,8) armchair graphene nanoribbon with Fe atoms at substitutional sites is investigated by density functional theory in combination with the non-equilibrium Greens function technique. For specific arrangements, a high degree of spin polarisation is achieved. These include a single substitution at an edge position or double substitution in the central sector of the transmission element. The possibility of switching between majority and minority spin polarisation by changing the double substitution geometry is predicted. Including the bias dependence of the transmission function proves to be essential for correct representation of the spin-resolved current-voltage profiles.

Thermal rate constants of beryllium clusters in gas phase

Abstract Formation and fragmentation of beryllium clusters up to 100 atoms were studied using molecular dynamics trajectory simulations. Association rate constants of a single Be atom attachment to Ben clusters, n = 2-20, 30, 40, 50, 60, 70, 80, 90 and 100, and dissociation rate constants of these clusters were calculated directly. Dependence of the dissociation rate constants on temperature is strong and follows the Arrhenius equation. An analysis of the dissociation reactions has shown that beryllium clusters dissociate mainly into single Be atoms. The monomer association reaction depends weakly on temperature but strongly on the size of the cluster.