Molecular dynamics investigation of the self-diffusion of binary mixture diffusion in the metal-organic framework Zn(tbip) accounting for framework flexibility

Seehamart, Kompichit; Chmelik, Christian; Krishna, Rajamani; Fritzsche, Siegfried

doi:10.1016/j.micromeso.2011.02.018

Cited by 12 publications

(9 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another recent MD study examined the self diffusivities of equimolar CO 2 /ethane, CH 4 /ethane and CO 2 /methanol mixtures in Zn(tbip) including the flexibility effects. (Seehamart et al, 2011) Similar to previous observations, faster diffusing molecules accelerate the slower diffusing molecules whereas the slower ones slow down the faster ones through the channel of Zn(tbip).…”

Section: Mixture Diffusionsupporting

confidence: 86%

Recent Advances in Molecular Dynamics Simulations of Gas Diffusion in Metal Organic Frameworks

Keskın¹

2012

Molecular Dynamics - Theoretical Developments and Applications in Nanotechnology and Energy

View full text Add to dashboard Cite

Section: Mixture Diffusionsupporting

confidence: 86%

Recent Advances in Molecular Dynamics Simulations of Gas Diffusion in Metal Organic Frameworks

Keskın¹

2012

Molecular Dynamics - Theoretical Developments and Applications in Nanotechnology and Energy

View full text Add to dashboard Cite

“…It has been demonstrated that gas diffusivity in MOFs is severely underestimated by assuming a rigid model when the pore size is comparable to the size of guest molecules. 5 For this case, structural flexibility should be taken into account. In addition, the inclusion of flexibility is prerequisite to simulate framework rearrangement when MOFs distort under external stimuli (e.g., temperature, pressure, or sorption).…”

Section: Introductionmentioning

confidence: 99%

“…[13][14][15] By assuming structural flexibility, Krishna and co-workers simulated the diffusion of gases in Zn(tbip). 5,16 In addition, the structural transition of DMOF-1 upon benzene adsorption was studied by using a fully flexible force field. 17 Nevertheless, flexible force fields for most MOFs are generally not available.…”

Section: Introductionmentioning

confidence: 99%

Development of a force field for zeolitic imidazolate framework-8 with structural flexibility

Hu¹,

Zhang²,

Jiang³

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

A force field is developed for zeolitic imidazolate framework-8 (ZIF-8) with structural flexibility by combining quantum chemical calculations and classical Amber force field. The predicted crystalline properties of ZIF-8 (lattice constants, bond lengths, angles, dihedrals, and x-ray diffraction patterns) agree well with experimental results. A structural transition from crystalline to amorphous as found in experiment is observed. The mechanical properties of ZIF-8 are also described fairly well by the force field, particularly the Young's modulus predicted matches perfectly with measured value. Furthermore, the heat capacity of ZIF-8 as a typical thermophysical property is predicted and close to experimental data available for other metal-organic frameworks. It is revealed the structural flexibility of ZIF-8 exerts a significant effect on gas diffusion. In rigid ZIF-8, no diffusive behavior is observed for CH(4) within the simulation time scale of current study. With the structural flexibility, however, the predicted diffusivities of CH(4) and CO(2) are close to reported data in the literature. The density distributions and free energy profiles of CH(4) and CO(2) in the pore of ZIF-8 are estimated to analyze the mechanism of gas diffusion.

show abstract

“…These rigid framework simulations have been shown to accurately predict diffusivities for a variety of adsorbates in different MOFs, as evidenced in the previous sections; however, some MOFs have flexible linkages, such that pore sizes and shapes can change dramatically due to changes in temperature or adsorbate loading. MOFs can have dramatic thermal expansion coefficients [206] that impact simulated activation energies of diffusion, and some MOFs can restructure their pores at higher adsorbate loadings [207][208][209]. In some cases, local fluctuations of the framework structure may affect window sizes and influence diffusion as in zeolites.…”

Section: Flexible Microporous Metal-organic Frameworkmentioning

confidence: 99%

Connecting theory and simulation with experiment for the study of diffusion in nanoporous solids

et al. 2021

View full text Add to dashboard Cite

Nanoporous solids are ubiquitous in chemical, energy, and environmental processes, where controlled transport of molecules through the pores plays a crucial role. They are used as sorbents, chromatographic or membrane materials for separations, and as catalysts and catalyst supports. Defined as materials where confinement effects lead to substantial deviations from bulk diffusion, nanoporous materials include crystalline microporous zeotypes and metal–organic frameworks (MOFs), and a number of semi-crystalline and amorphous mesoporous solids, as well as hierarchically structured materials, containing both nanopores and wider meso- or macropores to facilitate transport over macroscopic distances. The ranges of pore sizes, shapes, and topologies spanned by these materials represent a considerable challenge for predicting molecular diffusivities, but fundamental understanding also provides an opportunity to guide the design of new nanoporous materials to increase the performance of transport limited processes. Remarkable progress in synthesis increasingly allows these designs to be put into practice. Molecular simulation techniques have been used in conjunction with experimental measurements to examine in detail the fundamental diffusion processes within nanoporous solids, to provide insight into the free energy landscape navigated by adsorbates, and to better understand nano-confinement effects. Pore network models, discrete particle models and synthesis-mimicking atomistic models allow to tackle diffusion in mesoporous and hierarchically structured porous materials, where multiscale approaches benefit from ever cheaper parallel computing and higher resolution imaging. Here, we discuss synergistic combinations of simulation and experiment to showcase theoretical progress and computational techniques that have been successful in predicting guest diffusion and providing insights. We also outline where new fundamental developments and experimental techniques are needed to enable more accurate predictions for complex systems.

show abstract

Molecular dynamics investigation of the self-diffusion of binary mixture diffusion in the metal-organic framework Zn(tbip) accounting for framework flexibility

Cited by 12 publications

References 19 publications

Recent Advances in Molecular Dynamics Simulations of Gas Diffusion in Metal Organic Frameworks

Recent Advances in Molecular Dynamics Simulations of Gas Diffusion in Metal Organic Frameworks

Development of a force field for zeolitic imidazolate framework-8 with structural flexibility

Connecting theory and simulation with experiment for the study of diffusion in nanoporous solids

Contact Info

Product

Resources

About