Noble Gas Adsorption in Metal–Organic Frameworks Containing Open Metal Sites

2014 ◽  
Vol 118 (22) ◽  
pp. 11685-11698 ◽  
Author(s):  
John J. Perry ◽  
Stephanie L. Teich-McGoldrick ◽  
Scott T. Meek ◽  
Jeffery A. Greathouse ◽  
Maciej Haranczyk ◽  
...  
2015 ◽  
Vol 3 (46) ◽  
pp. 23539-23548 ◽  
Author(s):  
Hakan Demir ◽  
Jeffery A. Greathouse ◽  
Chad L. Staiger ◽  
John J. Perry IV ◽  
Mark D. Allendorf ◽  
...  

Density functional theory (DFT) based force fields (FFs) for Ar and Xe adsorption in M-MOF-74 (M = Co, Ni, Zn, Mg), ZIF-8 and HKUST-1 were developed using three DFT functionals (PBE-D2, vdW-DF, vdW-DF2) in periodic systems.


Adsorption ◽  
2019 ◽  
Vol 26 (5) ◽  
pp. 663-685 ◽  
Author(s):  
Kristina Sladekova ◽  
Christopher Campbell ◽  
Calum Grant ◽  
Ashleigh J. Fletcher ◽  
José R. B. Gomes ◽  
...  

AbstractThe interactions between metal–organic frameworks (MOFs) and adsorbates have been increasingly predicted and studied by computer simulations, particularly by Grand-Canonical Monte Carlo (GCMC), as this method enables comparing the results with experimental data and also provides a degree of molecular level detail that is difficult to obtain in experiments. The assignment of atomic point charges to each atom of the framework is essential for modelling Coulombic interactions between the MOF and the adsorbate. Such interactions are important in adsorption of polar gases like water or carbon dioxide, both of which are central in carbon capture processes. The aim of this work is to systematically investigate the effect of varying atomic point charges on adsorption isotherm predictions, identify the underlying trends, and based on this knowledge to improve existing models in order to increase the accuracy of gas adsorption prediction in MOFs. Adsorption isotherms for CO2 and water in several MOFs were generated with GCMC, using the same computational parameters for each material except framework point charge sets that were obtained through a wide range of computational approaches. We carried out this work for 6 widely studied MOFs; IRMOF-1, MIL-47, UiO-66, CuBTC, Co-MOF-74 and SIFSIX-2-Cu-I. We included both MOFs with and without open metal sites (OMS), specifically to investigate whether this property affects the predicted adsorption behaviour. Our results show that point charges obtained from quantum mechanical calculations on fully periodic structures are generally more consistent and reliable than those obtained from either cluster-based QM calculations or semi-empirical approaches. Furthermore, adsorption in MOFs that contain OMS is much more sensitive to the point charge values, with particularly large variability being observed for water adsorption in such MOFs. This suggests that particular care must be taken when simulating adsorption of polar molecules in MOFs with open metal sites to ensure that accurate results are obtained.


2013 ◽  
Vol 15 (23) ◽  
pp. 9093 ◽  
Author(s):  
Marie V. Parkes ◽  
Chad L. Staiger ◽  
John J. Perry IV ◽  
Mark D. Allendorf ◽  
Jeffery A. Greathouse

2019 ◽  
Author(s):  
Andrew Rosen ◽  
M. Rasel Mian ◽  
Timur Islamoglu ◽  
Haoyuan Chen ◽  
Omar Farha ◽  
...  

<p>Metal−organic frameworks (MOFs) with coordinatively unsaturated metal sites are appealing as adsorbent materials due to their tunable functionality and ability to selectively bind small molecules. Through the use of computational screening methods based on periodic density functional theory, we investigate O<sub>2</sub> and N<sub>2</sub> adsorption at the coordinatively unsaturated metal sites of several MOF families. A variety of design handles are identified that can be used to modify the redox activity of the metal centers, including changing the functionalization of the linkers (replacing oxido donors with sulfido donors), anion exchange of bridging ligands (considering μ-Br<sup>-</sup>, μ-Cl<sup>-</sup>, μ-F<sup>-</sup>, μ-SH<sup>-</sup>, or μ-OH<sup>-</sup> groups), and altering the formal oxidation state of the metal. As a result, we show that it is possible to tune the O<sub>2</sub> affinity at the open metal sites of MOFs for applications involving the strong and/or selective binding of O<sub>2</sub>. In contrast with O<sub>2</sub> adsorption, N<sub>2</sub> adsorption at open metal sites is predicted to be relatively weak across the MOF dataset, with the exception of MOFs containing synthetically elusive V<sup>2+</sup> open metal sites. As one example from the screening study, we predict that exchanging the μ-Cl<sup>-</sup> ligands of M<sub>2</sub>Cl<sub>2</sub>(BBTA) (H<sub>2</sub>BBTA = 1<i>H</i>,5<i>H</i>-benzo(1,2-d:4,5-d′)bistriazole) with μ-OH<sup>-</sup> groups would significantly enhance the strength of O<sub>2</sub> adsorption at the open metal sites without a corresponding increase in the N<sub>2</sub> affinity. Experimental investigation of Co<sub>2</sub>Cl<sub>2</sub>(BBTA) and Co<sub>2</sub>(OH)<sub>2</sub>(BBTA) confirms that the former exhibits only weak physisorption, whereas the latter is capable of chemisorbing O<sub>2</sub> at room temperature. The chemisorption behavior is attributed to the greater electron-donating character of the μ-OH<sup>-</sup><sub> </sub>ligands and the presence of H-bonding interactions between the μ-OH<sup>-</sup> bridging ligands and the O<sub>2</sub> adsorbate.</p>


2020 ◽  
Author(s):  
Ali Raza ◽  
Arni Sturluson ◽  
Cory Simon ◽  
Xiaoli Fern

Virtual screenings can accelerate and reduce the cost of discovering metal-organic frameworks (MOFs) for their applications in gas storage, separation, and sensing. In molecular simulations of gas adsorption/diffusion in MOFs, the adsorbate-MOF electrostatic interaction is typically modeled by placing partial point charges on the atoms of the MOF. For the virtual screening of large libraries of MOFs, it is critical to develop computationally inexpensive methods to assign atomic partial charges to MOFs that accurately reproduce the electrostatic potential in their pores. Herein, we design and train a message passing neural network (MPNN) to predict the atomic partial charges on MOFs under a charge neutral constraint. A set of ca. 2,250 MOFs labeled with high-fidelity partial charges, derived from periodic electronic structure calculations, serves as training examples. In an end-to-end manner, from charge-labeled crystal graphs representing MOFs, our MPNN machine-learns features of the local bonding environments of the atoms and learns to predict partial atomic charges from these features. Our trained MPNN assigns high-fidelity partial point charges to MOFs with orders of magnitude lower computational cost than electronic structure calculations. To enhance the accuracy of virtual screenings of large libraries of MOFs for their adsorption-based applications, we make our trained MPNN model and MPNN-charge-assigned computation-ready, experimental MOF structures publicly available.<br>


2020 ◽  
Vol 124 (49) ◽  
pp. 26801-26813
Author(s):  
Dayton J. Vogel ◽  
Zachary R. Lee ◽  
Caitlin A. Hanson ◽  
Susan E. Henkelis ◽  
Caris M. Smith ◽  
...  

2012 ◽  
Vol 51 (9) ◽  
pp. 4947-4953 ◽  
Author(s):  
Zhangjing Zhang ◽  
Shengchang Xiang ◽  
Kunlun Hong ◽  
Madhab, C. Das ◽  
Hadi D. Arman ◽  
...  

2016 ◽  
Vol 138 (10) ◽  
pp. 3371-3381 ◽  
Author(s):  
Yong Yan ◽  
Michal Juríček ◽  
François-Xavier Coudert ◽  
Nicolaas A. Vermeulen ◽  
Sergio Grunder ◽  
...  

ChemSusChem ◽  
2017 ◽  
Vol 10 (7) ◽  
pp. 1543-1553 ◽  
Author(s):  
Nicolas Chanut ◽  
Sandrine Bourrelly ◽  
Bogdan Kuchta ◽  
Christian Serre ◽  
Jong-San Chang ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document