L. Vanduyfhuys

A breathing zirconium metal-organic framework with reversible loss of crystallinity by correlated nanodomain formation

B. Bueken, F. Vermoortele, M.J. Cliffe, M.T. Wharmby, D. Foucher, J. Wieme, L. Vanduyfhuys, C. Martineau, N. Stock, F. Taulelle, V. Van Speybroeck, A.L. Goodwin, D. De Vos
Chemistry - A European Journal
2016, 22, 1-5
2016
A1

Abstract 

The isoreticular analogue of the metal–organic framework UiO-66(Zr), synthesized with the flexible trans-1,4-cyclohexanedicarboxylic acid as linker, shows a peculiar breathing behavior by reversibly losing long-range crystalline order upon evacuation. The underlying flexibility is attributed to a concerted conformational contraction of up to two thirds of the linkers, which breaks the local lattice symmetry. X-ray scattering data are described well by a nanodomain model in which differently oriented tetragonal-type distortions propagate over about 7–10 unit cells.

Mechanical energy storage performance of an aluminum fumarate metal-organic framework

P.G. Yot, L. Vanduyfhuys, E. Alvarez, J. Rodriguez, J.-P. Itié, P. Fabry, N. Guillou, T. Devic, P.L. Llewellyn, V. Van Speybroeck, C. Serre, G. Maurin
Chemical Science
7, 446-450
2016
A1

Abstract 

The aluminum fumarate MOF A520 or MIL-53-FA is revealed to be a promising material for mechanical energy-related applications with performances in terms of work and heat energies which surpass those of any porous solids reported so far. Complementary experimental and computational tools are deployed to finely characterize and understand the pressure-induced structural transition at the origin of these unprecedented levels of performance.

Open Access version available at UGent repository

A comparison of barostats for the mechanical characterization of metal-organic frameworks

S.M.J. Rogge, L. Vanduyfhuys, A. Ghysels, M. Waroquier, T. Verstraelen, G. Maurin, V. Van Speybroeck
Journal of Chemical Theory and Computation (JCTC)
11 (12), 5583-5597
2015
A1

Abstract 

In this paper, three barostat coupling schemes for pressure control, which are commonly used in molecular dynamics simulations, are critically compared to characterise the rigid MOF-5 and the flexible MIL-53(Al) metal-organic frameworks. We investigate the performance of the three barostats, the Berendsen, the Martyna-Tuckerman-Tobias-Klein (MTTK) and the Langevin coupling methods, in reproducing the cell parameters and the pressure versus volume behaviour in isothermal-isobaric simulations. A thermodynamic integration method is used to construct the free energy profiles as a function of volume at finite temperature. It is observed that the aforementioned static properties are well reproduced with the three barostats. However, for static properties depending nonlinearly on the pressure, the Berendsen barostat might give deviating results as it suppresses pressure fluctuations more drastically. Finally, dynamic properties, which are directly related to the fluctuations of the cell, such as the time to transition from the large-pore to the closed-pore phase, cannot be well reproduced by any of the coupling schemes.

Fine-tuning the theoretically predicted structure of MIL-47(V) with the aid of powder X-ray diffraction

T. Bogaerts, L. Vanduyfhuys, D.E.P. Vanpoucke, J. Wieme, M. Waroquier, P. Van der Voort, V. Van Speybroeck
CrystEngComm
17, 8612–8622
2015
A1

Abstract 

The structural characterization of complex crystalline materials such as metal organic frameworks can prove a very difficult challenge both for experimentalists as for theoreticians. From theory, the flat potential energy surface of these highly flexible structures often leads to different geometries that are energetically very close to each other. In this work a distinction between various computationally determined structures is made by comparing experimental and theoretically derived X-ray diffractograms which are produced from the materials geometry. The presented approach allows to choose the most appropriate geometry of a MIL-47(V) MOF and even distinguish between different electronic configurations that induce small structural changes. Moreover the techniques presented here are used to verify the applicability of a newly developed force field for this material. The discussed methodology is of significant importance for modelling studies where accurate geometries are crucial, such as mechanical properties and adsorption of guest molecules.

Semi-Analytical mean-field model for predicting breathing in Metal-Organic Frameworks

L. Vanduyfhuys, A. Ghysels, S.M.J. Rogge, R. Demuynck, V. Van Speybroeck
Molecular Simulation
41, 16-17, 1311-1328
2015
A1

Abstract 

A new semi-analytical model is proposed to rationalize breathing of MIL-53 type materials. The model is applied on two case studies, the guest-induced breathing of MIL-53(Cr) with CO 2 and CH 4 , and the phase transformations for MIL-53(Al) upon xenon adsorption. Experimentally, MIL-53(Cr) breathes upon CO 2 adsorption, which was not observed for CH 4 . This result could be ascribed to the stronger interaction of carbon dioxide with the host matrix. For MIL-53(Al) a phase transition from the large pore phase could be enforced to an intermediate phase with volumes of about 1160 − 1300 A, which corresponds well to the phase observed experimentally upon xenon adsorption. Our thermodynamic model correlates nicely with the adsorption pressure model proposed by Coudert et al. Furthermore the model can predict breathing behavior of other flexible materials, if the user can determine the free energy of the empty host, the interaction energy between a guest molecule and the host matrix and the pore volume accessible to the guest molecules. This will allow to generate the osmotic potential from which the equilibria can be deduced and the anticipated experimentally observed phase may be predicted.

Open Access version available at UGent repository

QuickFF: A program for a quick and easy derivation of force fields for Metal-Organic Frameworks from ab initio input

L. Vanduyfhuys, S. Vandenbrande, T. Verstraelen, R. Schmid, M. Waroquier, V. Van Speybroeck
Journal of Computational Chemistry
36, 13, 1015–1027
2015
A1

Abstract 

QuickFF is a software package to derive accurate force fields for isolated and complex molecular systems in a quick and easy manner. Apart from its general applicability, the program has been designed to generate force fields for metal-organic frameworks in an automated fashion. The force field parameters for the covalent interaction are derived from ab initio data. The mathematical expression of the covalent energy is kept simple to ensure robustness and to avoid fitting deficiencies as much as possible. The user needs to produce an equilibrium structure and a Hessian matrix for one or more building units. Afterward, a force field is generated for the system using a three-step method implemented in QuickFF. The first two steps of the methodology are designed to minimize correlations among the force field parameters. In the last step, the parameters are refined by imposing the force field parameters to reproduce the ab initio Hessian matrix in Cartesian coordinate space as accurate as possible. The method is applied on a set of 1000 organic molecules to show the easiness of the software protocol. To illustrate its application to metal-organic frameworks (MOFs), QuickFF is used to determine force fields for MIL-53(Al) and MOF-5. For both materials, accurate force fields were already generated in literature but they requested a lot of manual interventions. QuickFF is a tool that can easily be used by anyone with a basic knowledge of performing ab initio calculations. As a result, accurate force fields are generated with minimal effort.

Open Access version available at UGent repository

QuickFF: toward a generally applicable methodology to quickly derive accurate force fields for Metal-Organic Frameworks from ab initio input

L. Vanduyfhuys, S. Vandenbrande, T. Verstraelen, R. Schmid, M. Waroquier, V. Van Speybroeck
Journal of Computational Chemistry
2015
A1
Published while none of the authors were employed at the CMM

Metal-organic frameworks as potential shock absorbers: the case of the highly flexible MIL-53(Al)

P.G. Yot, Z. Boudene, J. Macia, D. Granier, L. Vanduyfhuys, T. Verstraelen, V. Van Speybroeck, T. Devic, C. Serre, G. Ferey, N. Stock, G. Maurin
Chemical Communications
50, 9462-9464
2014
A1

Abstract 

The mechanical energy absorption ability of the highly flexible; MIL-53(Al) MOF material was explored using a combination of; experiments and molecular simulations. A pressure-induced transition; between the large pore and the closed pore forms of this solid; was revealed to be irreversible and associated with a relatively large; energy absorption capacity. Both features make MIL-53(Al) the first; potential MOF candidate for further use as a shock absorber.

Open Access version available at UGent repository

Pages

Subscribe to RSS - L. Vanduyfhuys