Front Cover: Syntheses, Polymorphic Transformations, and Functions of Ionic Crystals Based on Mononuclear Bismuth(III) Complexes and Polyoxometalates (ChemNanoMat 5/2022)

Polyoxometalates (POMs) have been a popular motif in crystal engineering. In this work, seven ionic crystals based on Keggin- or Dawson-type POMs and mononuclear Bi(III) complexes were synthesized. The Bi(III) center exhibited triangular dodecahedron, square antiprism, or pseudo-cubic eight-coordination geometries, with DMSO or DMF as ligands. The ionic crystals showed polymorphic transformations, and high proton conductivities depending on the structure. More information can be found in the Research Article by Sayaka Uchida et al.