New molecular metals based on BEDO radical cation salts with the square planar Ni(CN)42− anion

Abstract

Two new radical cation salts based on bis(ethylenedioxy)tetrathiafulvalene (BEDO) with the square planar Ni(CN)₄²⁻ anion, (BEDO)₄Ni(CN)₄·4CH₃CN (1) and (BEDO)₅Ni(CN)₄·3C₂H₄(OH)₂ (2), were synthesized by electrocrystallization. The X-ray structural analysis, electrical transport and magnetotransport properties as well as the calculated Fermi surfaces are presented and discussed. Both salts show metallic properties down to 4.2 K. The nature of the Fermi surface of both salts is discussed and compared with those of other β″ type BEDO salts. On the basis of this comparison it is suggested that salt 2 is a likely candidate to exhibit magnetic breakdown and quantum interference effects in the magnetoresistance. It is shown that salt 1 exhibits unconventional magnetotransport behavior.