Organic Antiferromagnetic Metals Exhibiting Superconducting Transitions κ-(BETS)2FeX4 (X=Cl, Br): Drastic Effect of Halogen Substitution on the Successive Phase Transitions

The Highly Conducting Spin-Crossover Compound Combining Fe(III) Cation Complex with TCNQ in a Fractional Reduction State. Synthesis, Structure, Electric and Magnetic Properties

“…In such materials, conductivity is associated with mobile electrons in organic layers, whereas magnetism usually originates from localized spins of transition metal ions in insulating counterion layers. In particular, salts of BEDT-TTF and its selenium-substituted derivative bis(ethylenedithio)tetraselenafulvalene (BETS) have been shown to combine (super)conducting and paramagnetic [7][8][9][10] and even antiferromagnetic [11,12] and ferromagnetic properties [13]. Moreover, interaction between localized spins in insulating magnetic layers and itinerant spins in conducting organic layers was found to lead to new fascinating phenomena such as field-induced superconductivity observed on λ-(BETS) 2 FeCl 4 [14] and κ-(BETS) 2 FeBr 4 [15].…”

Temperature-pressure phase diagram and electronic properties of the organic metalκ−(BETS)2Mn[NZverev1, Kartsovnik2, Biberacher3 et al. 2010Phys. Rev. B2211444View full textAdd to dashboardCite

“…10 In such materials, conductivity is associated with electrons in organic layers whereas magnetism usually originates from localized spins of transition metal ions in insulating counterion layers. In particular, salts of BEDT-TTF and its selenium-substituted derivative bis͑ethylenedithio͒tetraselenafulvalene ͑BETS͒ have been shown to combine superconducting and paramagnetic 11 and even antiferromagnetic 12,13 properties. Moreover, interaction between localized spins in insulating magnetic layers and itinerant spins in conducting organic layers was found to lead to new fascinating phenomena such as field-induced superconductivity observed on -͑BETS͒ 2 FeCl 4 ͑Ref.…”

Antiferromagnetic Ordering in Organic Conductor λ-(BEDT-TTF)2GaCl4 Probed by 13C NMR

“…It exhibits an AF ordering in zero magnetic field accompanied by a metal-insulator transition at 8.3 K 19 . The 3d spins in λ-(BETS) 2 FeCl 4 were considered to play the primary role in the AF ordering, as in a similar system of κ-(BETS) 2 FeX 4 (X = Cl, Br) 25,26 . However, Akiba et al performed specific heat measurements for λ-(BETS) 2 FeCl 4 and revealed that the 3d spin system shows a Schottky-like anomaly in the magnetic heat capacity below T N , and they suggested that the localized π electron system undergoes an AF ordering at T N , while the 3d spin system maintains a paramagnetic state under the effective magnetic field arising from the π−d interaction.…”