%0 Journal Article
%T Polymorphism and Metallic Behavior in BEDT-TTF Radical Salts with Polycyano Anions
%A Samia Benmansour
%A Mathieu Marchivie
%A Smail Triki
%A Carlos J. G¨®mez-Garc¨ªa
%J Crystals
%D 2012
%I MDPI AG
%R 10.3390/cryst2020306
%X Up to five different crystalline radical salts have been prepared with the organic donor BEDT-TTF and three different polynitrile anions. With the polynitrile dianion tcpd 2£¿ (=C[C(CN) 2] 3 2£¿), two closely related radical salts: ¦Á'-(ET) 4tcpd¡¤THF ( 1) (THF = tetrahydrofurane) and ¦Á'-(ET) 4tcpd¡¤H 2O ( 2) have been prepared, depending on the solvent used in the synthesis. With the mono-anion tcnoetOH £¿ (=[(NC) 2CC(OCH 2CH 2OH)C(CN) 2] £¿) two polymorphs with similar physical properties but different crystal packings have been synthesized: ¦È-(ET) 2(tcnoetOH) ( 3) and ¦Â''-(ET) 2(tcnoetOH) ( 4). Finally, with the mono-anion tcnoprOH £¿ (=[(NC) 2CC(OCH 2CH 2CH 2OH)C(CN) 2] £¿) we have prepared a metallic radical salt: ¦Â''-(ET) 2(tcnoprOH)(CH 2Cl 2CH 3Cl) 0.5 ( 5). Salts 1£¿ 4 are semiconductors with high room temperature conductivities and activation energies in the range 0.1¨C0.5 eV, whereas salt 5 is metallic down to 0.4 K although it does not show any superconducting transition above this temperature.
%K bis(ethylenedithio)tetrathiafulvalene
%K polycyano anions
%K molecular conductors
%K synthetic metals
%U http://www.mdpi.com/2073-4352/2/2/306