Polarity study of some 1-alkyl-3-methylimidazolium ambient-temperature ionic liquids with the solvatochromic dye, Nile Red

The polarity of ambient-temperature ionic liquids based on the 1-alkyl-3-methylimidazolium cation was probed using the solvatochromic dye Nile Red. The polarity of these liquids was shown to be comparable to that of the lower alcohols. The effects on polarity with changing anion and 1-alkyl group are reported. Copyright © 2000 John Wiley & Sons, Ltd.