[Ni(dmit)(2)] salts with supramolecular cation structure

The dithio late complex, [Ni(dmit)(2)] (dmit = 2-thioxo-1,3-dithiol-4,5-dit hiolate) is an organic pi-molecule which gives highly conducting salts with closed shell cations or organic donors, We have found that crown ether mac rocycles can be incorporated into the salts in which the crown ethers inclu de alkali metal cations forming supramolecular cation (SC) structures, The SC structural diversity was observed to depend on the size of the crown eth er and cation. Three kinds of crown ethers, 12-crown-4, 15-crown-5 and 18-c rown-6 in addition to an acyclic polyether analog of pentaetyleneglycol wer e incorporated in the conducting [Ni(dmit)(2)] crystals. The structure of t hese crystals will be described with emphasis on both the structures of SC and Ni(dmit)(2) conducting layers. In one example, the crown ether forms a channel in which the cation has a translational freedom. The cation, otherw ise merely forms a periodic Coulomb potential in the crystal, can influence the electrical conduction through the motion in the channel. The monovalen t [Ni(dmit)(2)] salts, which are possible candidates for molecular magnets will be described on a salt having SC structure. (C) 2000 Elsevier Science S.A. All rights reserved.