Sorption−Desorption Behavior of Bispyrazolato−Copper(II) 1D Coordination Polymers

A new polycrystalline <i>vapochromic</i> polymorph of the one-dimensional copper bispyrazolate polymer reversibly and selectively absorbs a number of small molecules; the crystal structures of the anhydrous and fully hydrated species, determined by powder diffraction methods, are markedly different despite their simple, fast, and reversible interconversion.