Magnetic/conducting hybrid compound composed of 1-D chain [Mn₂^IICl₅(EtOH)]_∞ ^- and BEDT-TTF stacking layer

An assembled compound (BEDT-TTF)₂[Mn₂Cl₅(EtOH)] (1) consisting of two structural lattices of Mn(II)-Cl one-dimensional (1-D) chains and bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) stacking layers was synthesized by electrochemical crystallization. Compound 1 crystallized in triclinic space group P-1 (#2) with a = 13.1628(5) Å, b = 20.3985(9) Å, c = 7.4966(3) Å, α = 98.3498(8)°, β = 104.980(1)°, γ = 74.602(2)°, V = 1868.3(1) ų, and Z = 2. The 1-D chains and the stacking layers are aligned along the c-axis of the unit cell. The 1-D chain is described as [Mn₂Cl₅(EtOH)]_∞^- in which two Mn(II) ions and four Cl^- ions form a ladder-like chain with Kagomé (cuboidal) sublattices, and the remaining Cl^- ion and an ethanol molecule cap the edge-positioned Mn(II) ions of the chains. The BEDT-TTF molecules are packed between the Mn-Cl chains (ac-plane), the intermolecular S⋯S contacts of which are approximately found in the range 3.440(2)-3.599(2) Å. The packing feature of BEDT-TTF molecules is very similar to that of (BEDT-TTF)₂ClO₄(TCE)_0.5 (TCE = 1,1,2-trichloroethane) (J. Am. Chem. Soc., 105, 297 (1983)). Regarding the electronic state of each BEDT-TTF molecule, Raman spectroscopic analysis and ESR study revealed the presence of half-valence BEDT-TTF molecules (charge delocalization) in 1. Magnetic measurements clearly demonstrated that the paramagnetic spins on the 1-D chain [Mn₂Cl₅(EtOH)]_∞^- arrange antiferromagnetically in the low-temperature region. Additionally, 1 exhibits metallic conductivity in the temperature range 2.0-300 K (σ = 21 S cm^-1 at 300 K and 1719 S cm^-1 at 2.0 K), due to the contribution of the stacked BEDT-TTFs. Consequently, these peculiarities that correspond to antiferromagnetic/metallic conductivity demonstrate the "bi-functionality" of 1.