Chemical Structure and Superconductivity

Abstract

Consideration of the chemical bonding topology of the conducting skeletons in the Chevrel phases MMo6S8 and the lanthanide rhodium borides LnRh4B4 indicates that the conducting skeletons consist of networks of edge-localized bonded atoms. These observations suggest that superconductivity is favored when electron mobility is restricted to fewer than three dimensions. Thus, the chemical bonding topologies of the highest T c superconductors contain one of the following features: (1) edge-localized M−M bonding in the conducting skeletons of ternary and quaternary solid-state superconductors or related, partially localized bonding in superconducting transition metals and their alloys; (2) localized rather than fully delocalized bonding in copper oxide superconductors containing Cu−O−Cu linkages with appreciable Cu···Cu antiferromagnetic interactions; or (3) surface-localized bonding in fullerene superconductors containing direct C−C bonds such as K3C60. In addition, heavy fermion superconductors with considerably lower T cs values are known in which the conducting skeleton consists of variable oxidation state lanthanide or actinide cations diluted by an anionic network of other metal atoms so that the lanthanide or actinide atoms are not within bonding distance of each other.

Aggregation and Deposition Kinetics of Fullerene (C60) Nanoparticles

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Novel Tin Structure Motives in Superconducting BaSn5 – The Role of Lone Pairs in Intermetallic Compounds [1]

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Coarse-Grained Modeling of the Titration and Conductance Behavior of Aqueous Fullerene Hexa Malonic Acid (FHMA) Solutions

“…Since its discovery in 1985, Buckminsterfullerene, C 60, has stimulated great interest due to its possible applications in biomedicine, , electronics, and optics . The fundamental structure of C 60 is well characterized, and in benzene, it has a hydrodynamic radius of 0.41 nm, which comes from measurement of its self-diffusion constant by 13 C pulsed-field gradient NMR .…”