Interaction of small gold clusters with carbon nanotube bundles: formation of gold atomicchains

Abstract

We use first-principles density functional theory to simulate the interaction of bundles ofsemiconducting (10, 0) and metallic (6, 6) carbon nanotubes (CNTs) with small gold clusters (Aun,n = 3, 5) inserted in their interstitial spaces. We find that gold clusters spontaneously evolve to formatomic chains along the axis of nanotubes and induce weak metallicity in the semiconductingnanotubes through charge transfer. We further show that a similar structural evolution ofPt3 clusters occurs in the interstitial spaces of a (10, 0) CNT bundle. Our calculations showthat these structural changes, along with interesting changes in the electronic structure,occur at moderate pressures that are readily achievable in a laboratory, and should berelevant to devices that make use of gold–nanotube contacts.