title: Structural diversity and physical properties of paramagnetic molecular conductors based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the tris(chloranilato)ferrate(III) complex.
abstract: Electrocrystallization of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) in the presence of the tris(chloranilato)ferrate(III) [Fe(Cl2An)3](3-) paramagnetic chiral anion in different stoichiometric ratios and solvent mixtures afforded three different hybrid systems formulated as [BEDT-TTF]3[Fe(Cl2An)3]·3CH2Cl2·H2O (1), δ-[BEDT-TTF]5[Fe(Cl2An)3]·4H2O (2), and α‴-[BEDT-TTF]18[Fe(Cl2An)3]3·3CH2Cl2·6H2O (3). Compound 1 presents an unusual structure without the typical alternating organic and inorganic layers, whereas compounds 2 and 3 show a segregated organic-inorganic crystal structure where layers formed by Λ and Δ enantiomers of the paramagnetic complex, together with dicationic BEDT-TTF dimers, alternate with layers where the donor molecules are arranged in the δ (2) and α‴ (3) packing motifs. Compound 1 behaves as a semiconductor with a much lower conductivity due to the not-layered structure and strong dimerization between the fully oxidized donors, whereas 2 and 3 show semiconducting behaviors with high room-temperature conductivities of ca. 2 S cm(-1) and 8 S cm(-1), respectively. The magnetic properties are dominated by the paramagnetic S = 5/2 [Fe(Cl2An)3](3-) anions whose high-spin character is confirmed by electron paramagnetic resonance and magnetic susceptibility measurements. The correlation between crystal structure and conductivity behavior was studied by means of tight-binding band structure calculations, which support the observed conducting properties.
authors.affiliation: Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari , S.S. 554 - Bivio per Sestu - I09042 Monserrato, Cagliari, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Atzori
authors.forename: Flavia
authors.initials: F
authors.lastname: Pop
authors.forename: Pascale
authors.initials: P
authors.lastname: Auban-Senzier
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Gómez-García
authors.forename: Enric
authors.initials: E
authors.lastname: Canadell
authors.forename: Flavia
authors.initials: F
authors.lastname: Artizzu
authors.forename: Angela
authors.initials: A
authors.lastname: Serpe
authors.forename: Paola
authors.initials: P
authors.lastname: Deplano
authors.forename: Narcis
authors.initials: N
authors.lastname: Avarvari
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Mercuri