1-Butyl-3-methylimidazolium tetrachloroferrate is a magnetic ionic liquid whose appearance resembles that of honey. It can be obtained from reacting 1-butyl-3-methylimidazolium chloride and ferric chloride resulting in a Lewis acid-base reaction. It has quite low water solubility. It is highly polar.
Due to the presence of the high spin anion , the liquid is paramagnetic and reportedly has a magnetic susceptibility of 40.6 × 10−6 emu g−1. A small neodymium magnet is able to attract this liquid in a test tube.
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