One-Dimensional CuBr₄^2- Ion Array and CuBr₃^- Ion Chain Included in the π Conducting Framework Composed of Bis(methylthio)tetrathiafulvalenothioquinone-1,3-dithiocarbonatodithiolemethide Molecules

Abstract

The reaction of a new donor molecule having a planar but largely bent skeleton, bis(methylthio)tetrathiafulvalenothioquinone-1,3-dithiocarbonatodithiolemethide (1), with CuBr(2) in CH(3)CN/CS(2) afforded a black-colored crystal with a formula of 1(4).CuBr(4).2CuBr(3). In the crystal 1 molecules are one-dimensionally stacked to form half-cut pipelike columns, which are arranged to construct two different shapes of channels included by a one-dimensional array of CuBr(4)(2)(-) ions and a bibromide-bridged linear chain of CuBr(3)(-) ions with a square-pyramidal geometry at the Cu atom, [CuBr(3)(-)](n)(), respectively. The room-temperature electrical conductivity on the single crystal of 1(4).CuBr(4).2CuBr(3) was 2.0 x 10(-)(2) S cm(-)(1), and the temperature dependence of electrical conductivity was semiconducting with a large activation energy of 160 meV. The interactions between the neighboring Cu(II) d spins in the one-dimensional S = 1/2 spin systems due to CuBr(4)(2)(-) ions and CuBr(3)(-) ions in [CuBr(3)(-)](n)() were both antiferromagnetic, and the magnitudes were moderate (Weiss temperature, THETAV; = -18 K) in the former spin system and fairly large (coupling constant, J/k(B) = -120 K) in the latter spin system, which was in marked contrast to a moderate and ferromagnetic [CuBr(3)(-)](n)() chain in the cyclohexylammonium salt already known.

RCNSSS+: A novel class of stable sulfur rich radical cations

“…This structural and magnetic diversity is on par with that observed for TTF +• radical cation [87,89,90], although we note that TTF +• is not totally sulfur based. The manipulation of bulk magnetic properties by manipulation of anion size is also possible as has been demonstrated in the series of 24 2+ [A − ] 2 (A = AsF 6 , SbF 6 , Sb 2 F 11 ) and almost certainly will be the case for other derivatives of RCNSSS +• .…”

“…In the majority of these structures, face-to-face or slipped dimers are formed with the intra-dimeric separation falling in the range 3.25-3.5Å [89]. Monomeric examples of TTF +• are much rarer but not unknown [90].…”

Theoretical studies on magnetic interaction in one‐dimensional spin chains of hydrogen atoms (Hn) and copper bromide (CunBrm)

“…The superconductivity induced by external magnetic field also was reported in λ‐phase salts 12. Here we focus on Cu n Br m chain in the complex 13. Magnetic behaviors were investigated by several ab initio methods in detail.…”

“…Sugimoto and coworkers reported crystal structure of 1 4 · CuBr 4 · 2CuBr 3 13 as illustrated in Figure 6(A). The X‐ray diffraction data were collected at 93 K, and calculated positions of the hydrogen atoms were included.…”

“…Very recently, Sugimoto and coworkers reported synthesis and experimental studies for new complex of tetrathiafulvalene (TTF)‐derivative donor ( 1 4 · CuBr 4 · 2CuBr 3 ) 13. Magnetic properties behave ferromagnetically and antiferromagnetically with structural changing.…”