Coordination polymers and metal-organic frameworks: materials by design.

The field of coordination polymers and metal–organic frameworks (MOFs) has evolved over a period of approximately 25 years to a stage where it is one of the most widely investigated areas of materials chemistry. The field has impacted many areas of science including commercial applications from gas storage agents to new investigations as drug-delivery vehicles [1]. Coordination polymers and MOFs are prepared from the combination of metal cations, commonly dor f-block metals, and ligands capable of bridging metal centres to create polymeric structures which extend in one, two or three dimensions. The key features of coordination networks and MOFs that make them so attractive to researchers from many fields are their regular structure and the positioning of components in three-dimensional space. The beauty of MOFs lies in the fact that through a basic understanding of coordination chemistry, tracing all the way back to the original discoveries of Werner, the careful chemist can use relatively robust and predictable coordination bonds to position different components of a polymeric framework structure with respect to one another. This important feature of MOFs allows researchers to manipulate structures at the molecular level within polymeric framework structures and hence to modify the properties of the resulting materials. It is this basic premise which underscores the contribution and promise of MOFs in so many fields.