Magnetization Studies of Superconductivity in a Molecular Metal Cluster Compound

Abstract

Abstract Magnetization studies of the superconducting phases of two representative examples of the metal cluster compounds [Ga 84 {N(SiMe 3 ) 2 } 20 ‐Li 6 Br 2 (thf) 20 ]·2toluene are presented. These materials can be seen as self‐organized nanostructures, composed of identical nanosized Ga 84 metal particles arranged in a crystalline ordered 3‐dimensional array with a weak interparticle charge transfer. The compounds undergo transitions to bulk superconductivity of type II below T c ≈ 7 – 8 K. The lower and upper critical fields B c1 and B c2 vary greatly between samples, which can be attributed to different concentrations of lattice defects arising from toluene deficiency.