LITHIUM-ETHYLAMINE AND LITHIUM-SODIUM-ETHYLAMINE SYSTEMS - A NONMETALLIC LIQUID ELECTRIDE AND THE LOWEST MELTING FUSED SALT

Phase equilibria and compound formation in two new alkali metal-amine systems were studied by differential thermal analysis (DTA), EPR, NMR, and magnetic susceptibility methods. Lithium and ethylamine (EtNH(2)) mixtures with the nominal formula Li(EtNH(2))(n) were studied for n = 2-16. A eutectic with n approximate to 5 melting at T-E = 176.5 +/- 0 .5 K is present. The presence of an endotherm at T-E from n = 2-16 pre cludes the existence of solid compounds in this composition range unle ss they melt with decomposition at the eutectic temperature or decompo se at the temperature of a solid-solid transition (T = 124 +/- 1 K). E PR line shapes indicate that neither the solid nor the solutions are m etallic, and magnetic susceptibilities show that these deep blue-black systems are essentially diamagnetic. Samples that contained equimolar lithium and sodium in ethylamine, which had the nominal formula LiNa( EtNH(2))(n), were studied for n = 1-32. Alkali metal NMR studies show that Li+ and Na- are present in both the liquid and solid phases. A sh iny gold eutectic solution with n = 5-5.5 freezes at 171.3 +/- 0.5 K, and a compound with n = 4 melts incongruently at 217.8 +/- 0.4 K. Ther e is some evidence for compound formation with n = 2-3.