Molecular encapsulation of gases

The principles and techniques of molecular encapsulation, as applied to environmentally, biologically, and commercially important gases, are reviewed. The gases may be trapped within natural (clathrates, cyclodextrins) or synthetic (cryptophanes, carcerands, calixarenes) cavities. The physical and chemical features of the cavities are key to understanding which gases may be trapped and to what extent. These trapping materials possess a host of applications, from gas sensing and separation to acting as storage devices and microreaction vessels.