Long-Range and Coupled Rotor Dynamics in NO2-MIL-53(Al) by Classical Molecular Dynamics
Srinidhi Mula1, Joris Bierkens2, Louis Vanduyfhuys3
1Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands.
The Journal of Physical Chemistry. C, Nanomaterials and Interfaces
|December 5, 2024
Summary
Metal-organic frameworks (MOFs) exhibit correlated rotor dynamics in nitrofunctionalized MIL-53. Linker dynamics along the pore direction show a PNPNPN... arrangement, influencing neighboring linkers. This has implications for ferroelectric switching and diffusion control.
Area of Science:
- Materials Science
- Chemistry
- Physics
Background:
- Metal-organic frameworks (MOFs) offer tunable properties through control of linker dynamics.
- Nitrofunctionalized MIL-53, a terephthalate-based MOF, exhibits coupled rotor dynamics of organic linkers along the pore direction.
Purpose of the Study:
- To investigate the range and nature of correlated linker dynamics in nitrofunctionalized MIL-53 using molecular dynamics simulations.
- To understand the influence of linker conformation on neighboring dynamics and long-range correlations.
Main Methods:
- Classical molecular dynamics simulations were performed on supercells of nitrofunctionalized MIL-53.
- Analysis focused on the conformational arrangements and dynamics of organic linkers along the pore direction.
Main Results:
- An alternating planar (P) and nonplanar (N) linker conformation (PNPNPN...) was observed along the pore direction.
- Correlated dynamics were identified between direct and next-nearest neighboring linkers.
- 180° rotational flips of planar linkers induced changes in neighbor librations and reorientation of next-nearest planar neighbors.
Conclusions:
- Correlated linker dynamics occur over long length scales (nanoseconds) in nitrofunctionalized MIL-53.
- These dynamics are influenced by the steric environment and pore space, leading to specific conformational arrangements.
- The findings provide insights for designing MOFs with geared linker rotation for applications in ferroelectric switching and diffusion control.
Related Concept Videos
01:27¹H NMR: Long-Range Coupling
1.7K
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
1.7K
01:08Spin–Spin Coupling Constant: Overview
878
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
878
03:51Molecular Orbital Theory II
19.0K
Molecular Orbital Energy Diagrams
19.0K
01:12Fermi Level Dynamics
223
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
223
01:13¹H NMR: Complex Splitting
1.2K
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
1.2K
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
1.0K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.0K