[FeCl4]-ionic liquid based ferrofluids

Abstract

Magnetic ionic liquids derived from hydrochloride methyl ester alanine amino acids (AA) and FeCl3 were synthesized in ethanol and their magnetic properties were investigated. Iron (III) chloride forms ionic liquid in ethanol at saturated concentrations by the transfer of Cl- anion from one molecule of FeCl3 to the other molecule with the creation of tetrachloro ferrate anion [FeCl4]- as well as dimer [Fe2Cl7]-. Raman scattering indicates that after addition of hydrochloride methyl ester alanine to ethanol solutions of FeCl3 increase the intensities of signal at the frequencies at 318 cm -1 and 380 cm-1 as markers for the presence of [FeCl 4]- and [Fe2Cl7]- complexes. The magnetization at room temperature showed in both samples a linear dependence on the applied magnetic field. On the other hand, in the Raman scattering experiments the magnetization is smaller for FeCl3 sample in the presence of methyl ester alanine.