New ambient pressure organic superconductor with T-c=8.1 K based on unsymmetrical donor molecule, ethylenedithiotetrathiafulvalene: (EDT-TTF)(4)Hg3-delta I8, delta similar to 0.1-0.2

Abstract

The new ambient pressure organic superconductor based on unsymmetrical donor, ethylenedithiotetrathiafulvalene, and the iodomercurate anion. (EDT-TTF)(4)Hg3-deltaI8, delta similar to 0.1-0.2, with T-c = 8.1 K has been synthesized. Transport and magnetic properties have been investigated. Upper critical fields have been studied under parallel and perpendicular magnetic fields up to 17 T in the temperature region down to 1.3 K. The data show that upper critical fields are within the paramagnetic limit in all directions. The coherence lengths indicate that (EDT-TTT)(4)Hg3-deltaI8, delta similar to 0.1-0.2, is a quasi-two-dimensional organic superconductor. (C) 2003 Elsevier B.V. All rights reserved.