Berend Smit - Academia.edu (original) (raw)
Papers by Berend Smit
Angewandte Chemie, 2015
Molecular simulations and NMR relaxometry experiments demonstrate that pure benzene or xylene con... more Molecular simulations and NMR relaxometry experiments demonstrate that pure benzene or xylene confined in isoreticular metal-organic frameworks (IRMOFs) exhibit true vapor-liquid phase equilibria where the effective critical point may be reduced by tuning the structure of the MOF. Our results are consistent with vapor and liquid phases extending over many MOF unit cells. These results are counterintuitive since the MOF pore diameters are approximately the same length scale as the adsorbate molecules. As applications of these materials in catalysis, separations, and gas storage rely on the ability to tune the properties of adsorbed molecules, we anticipate that the ability to systematically control the critical point, thereby preparing spatially inhomogeneous local adsorbate densities, could add a new design tool for MOF applications.
Journal of the American Chemical Society, 2015
Porous covalent polymers are attracting increasing interest in the fields of gas adsorption, gas ... more Porous covalent polymers are attracting increasing interest in the fields of gas adsorption, gas separation, and catalysis due to their fertile synthetic polymer chemistry, large internal surface areas, and ultrahigh hydrothermal stabilities. While precisely manipulating the porosities of porous organic materials for targeted applications remains challenging, we show how a large degree of diversity can be achieved in covalent organic polymers by incorporating multiple functionalities into a single framework, as is done for crystalline porous materials. Here, we synthesized 17 novel porous covalent organic polymers (COPs) with finely-tuned porosities, a wide range of Brunauer-Emmett-Teller (BET) specific surface areas of 430-3624 m2 g-1, and a broad range of pore volumes of 0.24-3.50 cm3 g-1 - all achieved by tailoring the length and geometry of building blocks. Furthermore, we are the first to successfully incorporate more than three distinct functional groups into one phase for porous organic materials, which has been previously demonstrated in crystalline metal-organic frameworks (MOFs). COPs decorated with multiple functional groups in one phase can lead to enhanced properties that are not simply linear combinations of the pure component properties. For instance, in the dibromobenzene-lined frameworks, the bi- and multi-functionalized COPs exhibit selectivities for carbon dioxide over nitrogen twice as large as any of the singly-functionalized COPs. These multi-functionalized frameworks also exhibit a lower parasitic energy cost for carbon capture at typical flue gas conditions than any of the singly-functionalized frameworks. Despite the significant improvement, these frameworks do not yet outperform the current state-of-art technology for carbon capture. Nonetheless, the tuning strategy presented here opens up avenues for the design of novel catalysts, the synthesis of functional sensors from these materials, and the improvement in the performance of existing covalent organic polymers by multi-functionalization.
Physical Chemistry Chemical Physics, 2003
Metal-organic frameworks (MOFs) have attracted much attention over the past 20 years for their po... more Metal-organic frameworks (MOFs) have attracted much attention over the past 20 years for their possible applications in gas storage. In this study, we provide computational insight into what makes a MOF structure optimum for CO2 capture. We present a density functional theory-based study of the electronic and structural properties of recently synthesized frameworks M'3[(M4Cl)3(BTT)8]2, with M'=extraframework cation and M=Ca [1].
Greenhouse Gases: Science and Technology, 2013
The Journal of Physical Chemistry, 1988
Journal of the American Chemical Society, 2014
Disclaimer/Klachtenregeling Meent u dat de digitale beschikbaarstelling van bepaald materiaal inb... more Disclaimer/Klachtenregeling Meent u dat de digitale beschikbaarstelling van bepaald materiaal inbreuk maakt op enig recht dat u toekomt of uw (privacy)belangen schaadt, dan kunt u dit onderbouwd aan de Universiteitsbibliotheek laten weten. Bij een gegronde klacht zal de Universiteitsbibliotheek het materiaal ontoegankelijk maken en/of van de website verwijderen, dan wel samen met u bekijken hoe op een andere manier aan uw klacht tegemoet kan worden gekomen. Stuurt u hiervoor een e-mail naar: dare@uva.nl, of een brief naar: Bibliotheek van de Universiteit ...
The Journal of Physical Chemistry C, 2014
The Journal of Physical Chemistry C, 2013
Physical Review Letters, 1993
Physical Chemistry Chemical Physics, 2012
The self- and collective-diffusion behaviors of adsorbed methane, helium, and isobutane in zeolit... more The self- and collective-diffusion behaviors of adsorbed methane, helium, and isobutane in zeolite frameworks LTA, MFI, AFI, and SAS were examined at various concentrations using a range of molecular simulation techniques including Molecular Dynamics (MD), Monte Carlo (MC), Bennett-Chandler (BC), and kinetic Monte Carlo (kMC). This paper has three main results. (1) A novel model for the process of adsorbate movement between two large cages was created, allowing the formulation of a mixing rule for the re-crossing coefficient between two cages of unequal loading. The predictions from this mixing rule were found to agree quantitatively with explicit simulations. (2) A new approach to the dynamically corrected Transition State Theory method to analytically calculate self-diffusion properties was developed, explicitly accounting for nanoscale fluctuations in concentration. This approach was demonstrated to quantitatively agree with previous methods, but is uniquely suited to be adapted to a kMC simulation that can simulate the collective-diffusion behavior. (3) While at low and moderate loadings the self- and collective-diffusion behaviors in LTA are observed to coincide, at higher concentrations they diverge. A change in the adsorbate packing scheme was shown to cause this divergence, a trait which is replicated in a kMC simulation that explicitly models this behavior. These phenomena were further investigated for isobutane in zeolite MFI, where MD results showed a separation in self- and collective- diffusion behavior that was reproduced with kMC simulations.
Physica Scripta, 1996
Recent progress in the simulation of complex fluids is reviewed. It is shown that the use of rece... more Recent progress in the simulation of complex fluids is reviewed. It is shown that the use of recently developed Monte Carlo techniques allows the simulation of systems that several years ago were considered impossible to study via molecular simulations only. It is now possible to apply simulation techniques, which used to be limited to systems containing small molecules, to systems which are of interest for petrochemical applications. In this review, this development is illustrated by two examples of practical importance: the ...
Oil & Gas Science and Technology, 1996
Industrial applications of molecular simulations to determine thermodynamic properties usually in... more Industrial applications of molecular simulations to determine thermodynamic properties usually involve systems containing complex fluids. For these type of systems, in particular for systems containing long chain alkanes, the conventional simulation techniques are not sufficiently efficient. It is shown that the recently developed configurational-bias Monte Carlo technique is particularly suited to simulate the thermodynamic properties of these complex fluids. The use of this novel technique is illustrated with simulations on the adsorption of ...
Molecular Physics, 1995
Simulations of open systems are performed conveniently in the grand canonical ensemble. For chain... more Simulations of open systems are performed conveniently in the grand canonical ensemble. For chain molecules simulations of this type converge very poorly because of the very low probability of a successful insertion in the exchange step. Here, it is shown that the recently developed configurational-bias Monte Carlo technique can be used in a grand canonical Monte Carlo simulation to make the insertion of chain molecules possible. The use of this technique is illustrated by calculations of the adsorption isotherms of butane and hexane ...
Angewandte Chemie, 2015
Molecular simulations and NMR relaxometry experiments demonstrate that pure benzene or xylene con... more Molecular simulations and NMR relaxometry experiments demonstrate that pure benzene or xylene confined in isoreticular metal-organic frameworks (IRMOFs) exhibit true vapor-liquid phase equilibria where the effective critical point may be reduced by tuning the structure of the MOF. Our results are consistent with vapor and liquid phases extending over many MOF unit cells. These results are counterintuitive since the MOF pore diameters are approximately the same length scale as the adsorbate molecules. As applications of these materials in catalysis, separations, and gas storage rely on the ability to tune the properties of adsorbed molecules, we anticipate that the ability to systematically control the critical point, thereby preparing spatially inhomogeneous local adsorbate densities, could add a new design tool for MOF applications.
Journal of the American Chemical Society, 2015
Porous covalent polymers are attracting increasing interest in the fields of gas adsorption, gas ... more Porous covalent polymers are attracting increasing interest in the fields of gas adsorption, gas separation, and catalysis due to their fertile synthetic polymer chemistry, large internal surface areas, and ultrahigh hydrothermal stabilities. While precisely manipulating the porosities of porous organic materials for targeted applications remains challenging, we show how a large degree of diversity can be achieved in covalent organic polymers by incorporating multiple functionalities into a single framework, as is done for crystalline porous materials. Here, we synthesized 17 novel porous covalent organic polymers (COPs) with finely-tuned porosities, a wide range of Brunauer-Emmett-Teller (BET) specific surface areas of 430-3624 m2 g-1, and a broad range of pore volumes of 0.24-3.50 cm3 g-1 - all achieved by tailoring the length and geometry of building blocks. Furthermore, we are the first to successfully incorporate more than three distinct functional groups into one phase for porous organic materials, which has been previously demonstrated in crystalline metal-organic frameworks (MOFs). COPs decorated with multiple functional groups in one phase can lead to enhanced properties that are not simply linear combinations of the pure component properties. For instance, in the dibromobenzene-lined frameworks, the bi- and multi-functionalized COPs exhibit selectivities for carbon dioxide over nitrogen twice as large as any of the singly-functionalized COPs. These multi-functionalized frameworks also exhibit a lower parasitic energy cost for carbon capture at typical flue gas conditions than any of the singly-functionalized frameworks. Despite the significant improvement, these frameworks do not yet outperform the current state-of-art technology for carbon capture. Nonetheless, the tuning strategy presented here opens up avenues for the design of novel catalysts, the synthesis of functional sensors from these materials, and the improvement in the performance of existing covalent organic polymers by multi-functionalization.
Physical Chemistry Chemical Physics, 2003
Metal-organic frameworks (MOFs) have attracted much attention over the past 20 years for their po... more Metal-organic frameworks (MOFs) have attracted much attention over the past 20 years for their possible applications in gas storage. In this study, we provide computational insight into what makes a MOF structure optimum for CO2 capture. We present a density functional theory-based study of the electronic and structural properties of recently synthesized frameworks M'3[(M4Cl)3(BTT)8]2, with M'=extraframework cation and M=Ca [1].
Greenhouse Gases: Science and Technology, 2013
The Journal of Physical Chemistry, 1988
Journal of the American Chemical Society, 2014
Disclaimer/Klachtenregeling Meent u dat de digitale beschikbaarstelling van bepaald materiaal inb... more Disclaimer/Klachtenregeling Meent u dat de digitale beschikbaarstelling van bepaald materiaal inbreuk maakt op enig recht dat u toekomt of uw (privacy)belangen schaadt, dan kunt u dit onderbouwd aan de Universiteitsbibliotheek laten weten. Bij een gegronde klacht zal de Universiteitsbibliotheek het materiaal ontoegankelijk maken en/of van de website verwijderen, dan wel samen met u bekijken hoe op een andere manier aan uw klacht tegemoet kan worden gekomen. Stuurt u hiervoor een e-mail naar: dare@uva.nl, of een brief naar: Bibliotheek van de Universiteit ...
The Journal of Physical Chemistry C, 2014
The Journal of Physical Chemistry C, 2013
Physical Review Letters, 1993
Physical Chemistry Chemical Physics, 2012
The self- and collective-diffusion behaviors of adsorbed methane, helium, and isobutane in zeolit... more The self- and collective-diffusion behaviors of adsorbed methane, helium, and isobutane in zeolite frameworks LTA, MFI, AFI, and SAS were examined at various concentrations using a range of molecular simulation techniques including Molecular Dynamics (MD), Monte Carlo (MC), Bennett-Chandler (BC), and kinetic Monte Carlo (kMC). This paper has three main results. (1) A novel model for the process of adsorbate movement between two large cages was created, allowing the formulation of a mixing rule for the re-crossing coefficient between two cages of unequal loading. The predictions from this mixing rule were found to agree quantitatively with explicit simulations. (2) A new approach to the dynamically corrected Transition State Theory method to analytically calculate self-diffusion properties was developed, explicitly accounting for nanoscale fluctuations in concentration. This approach was demonstrated to quantitatively agree with previous methods, but is uniquely suited to be adapted to a kMC simulation that can simulate the collective-diffusion behavior. (3) While at low and moderate loadings the self- and collective-diffusion behaviors in LTA are observed to coincide, at higher concentrations they diverge. A change in the adsorbate packing scheme was shown to cause this divergence, a trait which is replicated in a kMC simulation that explicitly models this behavior. These phenomena were further investigated for isobutane in zeolite MFI, where MD results showed a separation in self- and collective- diffusion behavior that was reproduced with kMC simulations.
Physica Scripta, 1996
Recent progress in the simulation of complex fluids is reviewed. It is shown that the use of rece... more Recent progress in the simulation of complex fluids is reviewed. It is shown that the use of recently developed Monte Carlo techniques allows the simulation of systems that several years ago were considered impossible to study via molecular simulations only. It is now possible to apply simulation techniques, which used to be limited to systems containing small molecules, to systems which are of interest for petrochemical applications. In this review, this development is illustrated by two examples of practical importance: the ...
Oil & Gas Science and Technology, 1996
Industrial applications of molecular simulations to determine thermodynamic properties usually in... more Industrial applications of molecular simulations to determine thermodynamic properties usually involve systems containing complex fluids. For these type of systems, in particular for systems containing long chain alkanes, the conventional simulation techniques are not sufficiently efficient. It is shown that the recently developed configurational-bias Monte Carlo technique is particularly suited to simulate the thermodynamic properties of these complex fluids. The use of this novel technique is illustrated with simulations on the adsorption of ...
Molecular Physics, 1995
Simulations of open systems are performed conveniently in the grand canonical ensemble. For chain... more Simulations of open systems are performed conveniently in the grand canonical ensemble. For chain molecules simulations of this type converge very poorly because of the very low probability of a successful insertion in the exchange step. Here, it is shown that the recently developed configurational-bias Monte Carlo technique can be used in a grand canonical Monte Carlo simulation to make the insertion of chain molecules possible. The use of this technique is illustrated by calculations of the adsorption isotherms of butane and hexane ...