Polymorphism in formate-based dense metal-organic frameworks with the general formula ABX3 is predicted by quantum chemical calculations and confirmed experimentally. In particular [NH3NH2]Zn(HCOO)3 crystallizes in two different polymorphs, a perovskite-like framework and a chiral structure with hexagonal channels. A detailed thermodynamic analysis reveals that both structures are very close in free energy and that entropy driven effects are responsible for stabilizing the channel structure.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry