Definition

The MOF (Metal Organic Framework, i.e. three dimensional molecular structures) are a new class of compounds which form three-dimensional hollow structures, like spheres or cubes, with two special properties:

• increased specific surface area, which can be up to thousands of m² per gram of substance;
• one or more "apertures" through which atoms or small molecules can enter. 

The two features provide a glimpse of interesting developments. 
The increased surface allows catalysts to be deposited on it and therefore these compounds can be usefully employed in chemical reactions. The apertures of the same size as the atoms enable the storage of gases within these structures.