54763-34-7Relevant articles and documents
New Cation-Anion Interaction Motifs, Electronic Band Structure, and Electrical Behavior in β-(ET)2X Salts (X = ICl2- and BrICl-)
Emge, Thomas J.,Wang, Hau H.,Leung, Peter C. W.,Rust, Paul R.,Cook, Jan D.,et al.
, p. 695 - 702 (1986)
Two new organic metals, β-(ET)2ICl2 and β(ET)2BrICl, were synthesized, and their structures and electronic properties were characterized via X-ray diffraction, ESR studies, and band electronic stucture calculations.BEDT-TTF, abbreviated "ET", is bis(ethylenedithio)tetrathiafulvalene, C10S8H8.The packing of the ET molecules within the sheetlike network of these two isostructural salts is significantly different from that of the two-dimensional metals β-(ET)2X with the larger anions X- = I3-, I2Br-, IBr2-, and AuI2-, where all but X- = I2Br- are ambient-pressure superconductors.The ESR studies for the β-(ET)2ICl2 salt show that it is metallic down to ca. 22 K, at which temperature a metal-insulator transition is observed.The band electronic structures calculated for β-(ET)2ICl2 and β-(ET)2BrICl reveal that these salts are one-dimensional metals.Comparison of the stuctures and electronic properties of the β-(ET)2X salts with large linear anions (e.g., X- = I3-, I2Br-, IBr2-, and AuI2-) vs. those with the small symmetric (Cl-I-Cl)- and asymmetric (Br-I-Cl)- anions leads us to conclude that the nature of the interactions between ET molecules within a given sheetlike network, and hence the dimensionality of electrical properties, is strongly governed by the packing motif of ET molecules around a particular X- anion.
