Bethe–Salpeter Study of the Optical Absorption of trans and cis Azobenzene-Functionalized Metal–Organic Frameworks Using Molecular and Periodic Models

The optical absorption spectra of the azobenzene-functionalized metal-organic framework, PCN-123, are calculated in cis and trans configurations using the Bethe-Salpeter equation (BSE) formalism and the GW approximation using periodic and non-periodic models. In the visible, near-UV and mid-UV region the optical excitations in the MOF are associated with the azobenzene functionalities and this results in spectral features similar to the case of the gas phase azobenzene and the azo-functionalized ligand. The most noticeable difference is the significantly more intense S<sub>1</sub> band for cis in the MOF as compared to the free molecules which points to a faster and more complete cis→trans isomerization in the framework, with strong implications for the design of MOFs with high photoconversion efficiencies. Consistent with these findings, all the molecular models employed to represent the MOF, including the smallest, are found to yield a reasonable description of the low energy optical spectra (between 2 and 5 eV) of the periodic framework, with the exception of the stronger S<sub>1</sub> band of cis in the MOF, a feature that we attribute to a limitation of the fragment model to correctly represent the wavefunction of the extended framework.

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Bethe-Salpeter Study of the Optical Absorption of trans and cis Azobenzene-Functionalized Metal-Organic Frameworks using Molecular and Periodic Models

10.26434/chemrxiv.14043881.v1 ◽

2021 ◽

Author(s):

Aseem Rajan Kshirsagar ◽

Claudio Attaccalite ◽

Xavier Blase ◽

Jing Li ◽

Roberta Poloni

Keyword(s):

Optical Absorption ◽

Gas Phase ◽

Metal Organic Framework ◽

Molecular Models ◽

Gw Approximation ◽

Periodic Models ◽

Metal Organic ◽

Reasonable Description ◽

Cis And Trans ◽

In Cis

The optical absorption spectra of the azobenzene-functionalized metal-organic framework, PCN-123, are calculated in cis and trans configurations using the Bethe-Salpeter equation (BSE) formalism and the GW approximation using periodic and non-periodic models. In the visible, near-UV and mid-UV region the optical excitations in the MOF are associated with the azobenzene functionalities and this results in spectral features similar to the case of the gas phase azobenzene and the azo-functionalized ligand. The most noticeable difference is the significantly more intense S<sub>1</sub> band for cis in the MOF as compared to the free molecules which points to a faster and more complete cis→trans isomerization in the framework, with strong implications for the design of MOFs with high photoconversion efficiencies. Consistent with these findings, all the molecular models employed to represent the MOF, including the smallest, are found to yield a reasonable description of the low energy optical spectra (between 2 and 5 eV) of the periodic framework, with the exception of the stronger S<sub>1</sub> band of cis in the MOF, a feature that we attribute to a limitation of the fragment model to correctly represent the wavefunction of the extended framework.

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Taking Lanthanides out of Isolation: Tuning the Optical Properties of Metal-Organic Frameworks

10.26434/chemrxiv.11787534 ◽

2020 ◽

Author(s):

Samantha L. Anderson ◽

Davide Tiana ◽

Christopher Ireland ◽

Gloria Capano ◽

Maria Fumanal ◽

...

Keyword(s):

Optical Absorption ◽

Electronic Properties ◽

Rational Design ◽

Computational Study ◽

Water Solution ◽

Metal Organic Frameworks ◽

Visible Region ◽

Co Catalysts ◽

Optical And Electronic Properties ◽

Metal Organic

<div>Metal organic frameworks (MOFs) are increasingly used in applications that rely on the optical and electronic properties of these materials. These applications require a fundamental understanding on how the structure of these materials, and in particular the electronic interactions of the metal node and organic linker, determines these properties. </div><div><br></div><div>Herein, we report a combined experimental and computational study on two families of lanthanide-based MOFs: Ln-SION-1 and Ln-SION-2. Both comprise the same metal and ligand but with differing structural topologies. In the Ln-SION-2 series the optical absorption is dominated by the ligand and using different lanthanides has no impact on the absorption spectrum. The Ln-SION-1 series shows a completely different behavior in which the ligand and the metal node do interact electronically. By changing the lanthanide in Ln-SION-1, we were able to tune the optical absorption from the UV region to absorption that includes a large part of the visible region. For the early lanthanides we observe intraligand (electronic) transitions in the UV region, while for the late lanthanides a new band appears in the visible. DFT calculations showed that the new band in the visible originates in the spatial orbital overlap between the ligand and metal node. Our quantum calculations indicated that Ln-SION-1 with late lanthanides might be (photo)conductive. Experimentally, we confirm that these materials are weakly conductive and that with an appropriate co-catalysts they can generate hydrogen from a water solution using visible light. Our experimental and theoretical analysis provides fundamental insights for the rational design of Ln-MOFs with the desired optical and electronic properties.</div>

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A mild one-step method for enhancing optical absorption of amine-functionalized metal-organic frameworks

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2018.01.007 ◽

2018 ◽

Vol 227 ◽

pp. 190-197 ◽

Cited By ~ 29

Author(s):

Shan Gao ◽

Wanglai Cen ◽

Qian Li ◽

Jieyuan Li ◽

Yunfeng Lu ◽

...

Keyword(s):

Optical Absorption ◽

Metal Organic Frameworks ◽

Step Method ◽

Amine Functionalized ◽

Metal Organic ◽

One Step

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Computational Screening of Roles of Defects and Metal Substitution on Reactivity of Different Single- vs Double-Node Metal–Organic Frameworks for Sarin Decomposition

10.26434/chemrxiv.7755302 ◽

2019 ◽

Author(s):

MohammadReza MomeniTaheri ◽

Christopher J. Cramer

Keyword(s):

Heterogeneous Catalysts ◽

Metal Organic Frameworks ◽

Chemical Warfare Agent ◽

Metal Substitution ◽

Heterogeneous Catalytic ◽

Computational Screening ◽

Periodic Models ◽

Metal Organic ◽

Hydrolysis Of ◽

Defective Sites

Understanding how different factors affect the electronic prop-erties of metal-organic frameworks (MOFs) is critical to under-standing their potential for catalysis and to serve as catalyst supports. In this work, periodic dispersion corrected PBE cal-culations are performed to assess the catalytic activity of dif-ferent Zr6 vs Zr12 metal-organic frameworks (MOFs) for the heterogeneous catalytic hydrolysis of the chemical warfare agent (CWA) sarin. Using a comprehensive series of extended periodic models capable of capturing long-range sar-in/water/framework interactions in both Zr6 and Zr12 MOFs, the effect of numbers and morphologies of defective sites as well as ZrIV substitution with heavier CeIV are thoroughly in-vestigated. Our calculations show that hydrogen bonds in-volving both metal-oxide nodes and organic linkers can play important roles in the catalysis. Insights derived from this work should inform the design and realization of more effec-tive and robust next-generation MOF-based heterogeneous catalysts.

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Computational Screening of Roles of Defects and Metal Substitution on Reactivity of Different Single- vs Double-Node Metal–Organic Frameworks for Sarin Decomposition

10.26434/chemrxiv.7755302.v1 ◽

2019 ◽

Author(s):

MohammadReza MomeniTaheri ◽

Christopher J. Cramer

Keyword(s):

Heterogeneous Catalysts ◽

Metal Organic Frameworks ◽

Chemical Warfare Agent ◽

Metal Substitution ◽

Heterogeneous Catalytic ◽

Computational Screening ◽

Periodic Models ◽

Metal Organic ◽

Hydrolysis Of ◽

Defective Sites

Understanding how different factors affect the electronic prop-erties of metal-organic frameworks (MOFs) is critical to under-standing their potential for catalysis and to serve as catalyst supports. In this work, periodic dispersion corrected PBE cal-culations are performed to assess the catalytic activity of dif-ferent Zr6 vs Zr12 metal-organic frameworks (MOFs) for the heterogeneous catalytic hydrolysis of the chemical warfare agent (CWA) sarin. Using a comprehensive series of extended periodic models capable of capturing long-range sar-in/water/framework interactions in both Zr6 and Zr12 MOFs, the effect of numbers and morphologies of defective sites as well as ZrIV substitution with heavier CeIV are thoroughly in-vestigated. Our calculations show that hydrogen bonds in-volving both metal-oxide nodes and organic linkers can play important roles in the catalysis. Insights derived from this work should inform the design and realization of more effec-tive and robust next-generation MOF-based heterogeneous catalysts.

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Enhancing optical absorption of metal–organic frameworks for improved visible light photocatalysis

Chemical Communications ◽

10.1039/c3cc46398b ◽

2013 ◽

Vol 49 (90) ◽

pp. 10575-10577 ◽

Cited By ~ 157

Author(s):

Maxim A. Nasalevich ◽

Maarten G. Goesten ◽

Tom J. Savenije ◽

Freek Kapteijn ◽

Jorge Gascon

Keyword(s):

Optical Absorption ◽

Visible Light ◽

Metal Organic Frameworks ◽

Visible Light Photocatalysis ◽

Metal Organic

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Taking Lanthanides out of Isolation: Tuning the Optical Properties of Metal-Organic Frameworks

10.26434/chemrxiv.11787534.v1 ◽

2020 ◽

Author(s):

Samantha L. Anderson ◽

Davide Tiana ◽

Christopher Ireland ◽

Gloria Capano ◽

Maria Fumanal ◽

...

Keyword(s):

Optical Absorption ◽

Electronic Properties ◽

Rational Design ◽

Computational Study ◽

Water Solution ◽

Metal Organic Frameworks ◽

Visible Region ◽

Co Catalysts ◽

Optical And Electronic Properties ◽

Metal Organic

<div>Metal organic frameworks (MOFs) are increasingly used in applications that rely on the optical and electronic properties of these materials. These applications require a fundamental understanding on how the structure of these materials, and in particular the electronic interactions of the metal node and organic linker, determines these properties. </div><div><br></div><div>Herein, we report a combined experimental and computational study on two families of lanthanide-based MOFs: Ln-SION-1 and Ln-SION-2. Both comprise the same metal and ligand but with differing structural topologies. In the Ln-SION-2 series the optical absorption is dominated by the ligand and using different lanthanides has no impact on the absorption spectrum. The Ln-SION-1 series shows a completely different behavior in which the ligand and the metal node do interact electronically. By changing the lanthanide in Ln-SION-1, we were able to tune the optical absorption from the UV region to absorption that includes a large part of the visible region. For the early lanthanides we observe intraligand (electronic) transitions in the UV region, while for the late lanthanides a new band appears in the visible. DFT calculations showed that the new band in the visible originates in the spatial orbital overlap between the ligand and metal node. Our quantum calculations indicated that Ln-SION-1 with late lanthanides might be (photo)conductive. Experimentally, we confirm that these materials are weakly conductive and that with an appropriate co-catalysts they can generate hydrogen from a water solution using visible light. Our experimental and theoretical analysis provides fundamental insights for the rational design of Ln-MOFs with the desired optical and electronic properties.</div>

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Correction: Enhancing optical absorption of metal–organic frameworks for improved visible light photocatalysis

Chemical Communications ◽

10.1039/c4cc90482f ◽

2015 ◽

Vol 51 (5) ◽

pp. 961-962 ◽

Cited By ~ 7

Author(s):

Maxim A. Nasalevich ◽

Maarten G. Goesten ◽

Tom J. Savenije ◽

Freek Kapteijn ◽

Jorge Gascon

Keyword(s):

Optical Absorption ◽

Visible Light ◽

Metal Organic Frameworks ◽

Visible Light Photocatalysis ◽

Metal Organic

Correction for ‘Enhancing optical absorption of metal–organic frameworks for improved visible light photocatalysis’ by Maxim A. Nasalevich et al., Chem. Commun., 2013, 49, 10575–10577.

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