One of the potential solutions to separate light hydrocarbons in a cost efficient way is to use porous materials with selective chemical interactions. Metal-organic frameworks (MOFs) are good candidates of porous absorbents used in gas storage and separation, specifically for separation of ethylene and ethane.

In our group, we study how metal-organic frameworks, Fe-MOF-74 interacts with ethane. We analyse how the flexibility of the framework affects absorption, under different loading of ethane molecules. We place ethane molecules in the open coordination site of the framework and perform ab initio molecular dynamics simulations to understand adsorption of ethane by the framework. In particular, we are interested in performing these simulations including long-range van der Waals interactions, because long-range interactions play an important role in structural bonding of soft and porous materials, as in this case of MOFs. Our ab initio simulations provide important information to derive and test the quality of semi-empirical force field models.