Extreme molecular orientations in a dimorphic system: Polar/centric and polar/polar cogrowth crystal architectures

Abstract

(4-Pyrrolidinopyridyl)bis(acetylacetonato)zinc(II) forms perfectly polar as well as centrosymmetric crystal structures depending sensitively on the solvent and the rate of crystallization. Semiempirical computational modeling of molecular clusters, incorporating solvation effects, highlights the delicate balance of energetics involved in the solvent polarity preference of the extreme structures. A suitable choice of solvents provides crystals exhibiting an unusual cogrowth of polar/centric as well as polar/polar domains. This material provides a vivid illustration of the subtle nature of supramolecular assembly leading to extreme organizational motifs and opens up possibilities of realizing novel multidomain architectures in crystals.