Dramatic solid-state humidity-induced modification of the magnetic coupling in a dimeric fluorous copper(II)-carboxylate complex.

The very fast and efficient water vapor absorption of the dimeric fluorous copper(II)-carboxylate complex [Cu(2)(C(8)F(17)CO(2))(4)(acetone)(2)] (1) leads, in the solid state, to a dramatic decrease of the exchange magnetic coupling between the copper(II) ions and to a drastic change of its powder EPR spectrum.