Synthesis, Characterization, and Physical Properties of Two New Magnetic Organic Metals, [BEDT-TTF]4[C(CN)2CONH2]CuX2 (X = Cl and Br0.77Cl0.22)

Two new BEDT-TTF based charge transfer salts, [BEDT-TTF](4)[C(CN)(2)CONH2] CuX(2) (X = Cl and Br0.77Cl0.22) have been synthesized and characterized with use of x-ray diffraction, Energy Dispersive Spectroscopy (EDS), and Raman spectroscopy. ESR spectroscopy reveals that the anion layer contains 3% of paramagnetic Cu(II) species which exhibit Curie-Weiss behavior with a Weiss constant of theta = -2.8 K. Both compounds are metallic below 150 K. AC susceptibility, RF penetration depth, and RF impedance measurements under pressure do not reveal signals of superconductivity.