A.M. Kini, U. Geiser, H.H. Wang, K.D. Carlson, J.M. Williams, et al., "A new ambient-pressure organic superconductor, k-(ET)2Cu[N(CN)2]Br, with the highest transition temperature yet observed (inductive onset Tc = 11.6 K, resistive onset = 12.5 K)," Inorganic Chemistry, 29:2555-57, 1990.
Aravinda M. Kini (Argonne National Laboratory, Argonne, Ill.): "This paper reported the discovery of an organic superconductor with the highest Tc at ambient pressure reported to date. The compound is k-(ET)2Cu[N(CN)2]Br, where ET is the electron-donor molecule, bis(ethylenedithio)tetrathiaful-valene (Tc = 11.6 K at ambient pressure). The increment in Tc was about 1 K to 1.5 K over that of the previous record-holder, also an ET salt.
"More important, this find led to the preparation of additional (possibly superconducting!) cation-radical salts by use of various combinations of metal/pseudohalide/halide as counterionic species (salt synthesis-H. Wang; structure- U. Geiser). Halogen substitution led to the first isostructural k-phase salts, where "k" signifies a unique ...
