Novel organic magnetic conductors based on organochalcogen donors and an organic magnetic anion, TEMPO-NHCOCH 2SO 3−

Abstract

We report here four novel purely organic magnetic conductors containing common electron donors together with an organic anion including an organic free radical, (TTF)(TEMPO-NHCOCH 2SO 3)·0.5H 2O ( 1), (TMTSF)(TEMPO-NHCOCH 2SO 3)·2H 2O ( 2), (BEDT-TTF) 3(TEMPO-NHCOCH 2SO 3) 2·2H 2O ( 3), and α-(BEDT-TTF) 3(TEMPO-NHCOCH 2SO 3) 2·6H 2O ( 4). The TTF complex was prepared by metathesis of (TTF) 3(BF 4) 2 and the PPh 4 salt of the anion ( 5). The other complexes were obtained by electrocrystallization of the corresponding donors with the salt 5 as an electrolyte. Crystal structures of 2–4 have been solved. The salts 1 and 2 show relatively high resistivities (>10 7 and 5 × 10 3 Ω·cm), whilst the BEDT-TTF salts 3 and 4 have rather low room temperature resistivities (1.2 and 5.1 Ω·cm) with small activation energies (0.041 and 0.050 eV). The magnetic behavior of complex 1 obeys the Curie-Weiss law ( C = 0.379 emu·K/mol and θ = −3.29 K) and those of the other complexes obey the 1-D Heisenberg model ( C/ J = 0.366/−0.32 for 2, 0.373/−0.81 for 3, and 0.380 emu·K·mol −1/+0.42 K for 4). The relationships between the crystal structures and the physical properties are discussed.