Researchers at NIST have conducted a detailed computational study examining how different methods for calculating partial charges affect the simulated adsorption properties of IRMOF-3, a metal-organic framework known for its ability to capture carbon dioxide.
The study used the open-source Quantum ESPRESSO electronic structure calculator to compute the electronic structure of IRMOF-3 and generate electron density maps. Various methods were employed to calculate partial charges from these maps.
Monte Carlo molecular simulations were then performed to obtain the adsorption isotherms of CO2 in IRMOF-3 using different partial charge calculation methods. The study found that the choice of partial charge method significantly impacts the simulated adsorption properties of IRMOF-3.
The research provides valuable insights into the importance of accurate partial charge calculations in modeling the adsorption properties of metal-organic frameworks for carbon capture applications. The findings highlight the need for careful consideration of computational methods when simulating these materials for practical applications.
The study utilized density functional theory calculations with the PBE exchange-correlation functional and optimized lattice constants using damped dynamics. Adsorption simulations were performed using the TraPPE and DREIDING force fields with standard mixing rules. The results were obtained using Transition-matrix Monte Carlo simulations and bulk simulations of TraPPE CO2.
Keywords: Monte Carlo simulations, Electronic structure calculations, Quantum ESPRESSO
