Stabilization of the merocyanine form of photochromic compounds in fluoro alcohols is due to a hydrogen bond

Abstract

Fluoroalcohols [1,1,1,3,3,3-hexafluoropropan-2-ol (HFP), 2,2,2-trifluoroethanol (TFE) and 2-fluoroethanol (FE)], acting as Lewis acids, stabilize the π-conjugated, colored merocyanine forms of spiropyran and spirooxazine photochromic compounds as metal ions do.

References

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