Polymorphism in Hybrid Organic−Inorganic Bilayered Magnetic Conductors (BEDT-TTF)₃(Fe^IIICl₄)₂, BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene

Abstract

Two polymorphic hybrid organic-inorganic bilayered magnetic conductors (BEDT-TTF) 3 (FeCl 4 ) 2 (I and II) (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene) were obtained by the diffusion method. I crystallizes in a monoclinic system with cell parameters: a = 55.9187(7) Å , b = 6.7424(1) Å , c = 14.9057(3) Å , β = 101.056(1)°, V = 5515.5(2) Å 3 , Z = 4, and C2/c at 290 K, and it transforms to a triclinic system at 220 K: a = 13.4440 (2) Å , b = 14.6761(2) Å , c = 28.1529(5) Å , R = 100.738(1)°, β = 96.875(1)°, γ = 90.017(1)°, V = 5416.8(2) Å 3 , Z = 4 and P1 which is stable to 110 K. II crystallizes in a triclinic system with cell parameters: a = 6.7396(3) Å , b = 9.9640(5) Å , c = 21.132(1) Å , R = 79.536(2)°, β = 81.032(2)°, γ = 81.066(3)°, V = 1367.3(1) Å 3 , Z = 1, and P1 at 290 K. They both contain two donor layers having formal charge of BEDT-TTF þ0.5 in layer-A and BEDT-TTF þ1.0 in layer-B. The donor arrangements in layer-A are δ-type in I and β 0 -type in II, while the donor arrangements in layer-B and anion arrangements in I and II are also different. Layer-A is separated from layer-B by FeCl 4-. The energy band calculation indicates a Peierls-like metal-insulator transition in the transverse direction at 220 K in I (σ 300K = 120 S 3 cm -1 ), and a Mott insulating state in II (σ 300K = 10 -2 S 3 cm -1 and E R = 0.2 eV). The presence of π-d interactions between donors and anions results in the magnetic anomalies observed at 4.8 K in I and 2.7 K in II.

Highly Active and Recyclable Metal Oxide Catalysts for the Prins Condensation of Biorenewable Feedstocks

“…The Fe–Cl bond lengths and the Cl–Fe–Cl bond angles are in the range of 2.173(1) to 2.197(1) Å (mean 2.187 Å) and 107.59(1) to 112.59(1)° (mean 109.4°), respectively. The values are in the expected range found for other compounds containing tetrachloridoferrate(III) such as [Fe(L) 3 ][FeCl 4 ] 2 4e, [Fe(PDN) 2 (H 2 O) 2 ][FeCl 4 ] 2 · 4CH 3 NO 2 (PDN = p ‐phthalodinitrile)4i, [EDO‐TTFVO] 2 [FeCl 4 ] (EDO‐TTFVO = ethylenedioxy‐tetrathiafulvalenoquinone‐1, 3‐dithiolemethide)7a, (BEDT‐TTF) 3 [FeCl 4 ] 2 [BEDT‐TTF = bis(ethylenedithio)tetrathiafulvalene]7b [C 2 mim][FeCl 4 ] (C 2 mim = 1‐methyl‐3‐ethylimidazolium)7c, and [C 4 mim][FeCl 4 ] (C 4 mim = 1‐butyl‐3‐methylimidazolium) 7d. The shortest Fe III ··· Fe III distance is 6.6584(2) Å.…”

Solvent-Included Ternary Charge-Transfer Salt (BEDT-TTF)2GaCl4(C6H5Cl)0.5, (BEDT-TTF = Bis(ethyelenedithio)-tetrathiafulvalene)

“…It showed semiconductive behavior from 300 K to 150 K with E  = 0.124 eV and σ rt = 1 S , E  = 0.2 eV as expected from the donor arrangement as no dimerization was observed [3]. The conductivity is lower than the bilayered magnetic charge-transfer salt δ-(BEDT-TTF) 3 (FeCl 4 ) 2 because the conductivity in δ-(BEDT-TTF) 3 (FeCl 4 ) 2 is contributed to from both layer-A and layer-B with an anisotropic room-temperature conductivity range from 4.6~120 S·cm −1 [7]. This corresponds with the expectancy that the conductivity of the charge-transfers salts is dominated by the arrangement of the BEDT-TTF molecules.…”

“…New magnetic conductors can be expected when solvent molecules are intercalated into binary charge-transfer salts of FeCl 4 − [7].…”

Synthesis, Crystal Structure, and Characterization of the Charge‐Transfer Salt (BEDT‐TTF)[Fe(C2O4)Cl2](CH2Cl2), {BEDT‐TTF = Bis(ethylenedithio)tetrathiafulvalene}

“…Because the S ··· Cl and S ··· O contacts between the donors and the anions may have produced π‐d coupling, as observed in charge‐transfer salts of FeCl 4 – , the coupling between π and d moments should be considered. The calculated value with the Hückel method is J π d = 0.075 K (0.052 cm –1 ),16 which is weaker than the antiferromagnetic interactions between the oxalate‐bridged metal atoms and the π‐d coupling through S/Se ··· Cl contacts in the charge‐transfer salts λ‐BETS 2 FeCl 4 ( J π d = 16.72 K) and β″‐(BEDT‐TTF) 3 (FeCl 4 ) 2 ( J π d = 25.82 K) 16,17. The antiferromagnetic behavior of 1 is dominated by intra‐chain interactions through the oxalate‐bridge.…”