Transformation between 2D covalent organic frameworks with distinct pore hierarchy via exchange of building blocks with different symmetries

2020 ◽  
Vol 56 (98) ◽  
pp. 15418-15421
Author(s):  
De-Li Ma ◽  
Qiao-Yan Qi ◽  
Jian Lu ◽  
Meng-Hui Xiang ◽  
Chao Jia ◽  
...  
Keyword(s):  
Structural Transformation ◽  
Building Blocks ◽  
Covalent Organic Frameworks ◽  
Molecular Building Blocks

Direct structural transformation between 2D covalent organic frameworks (COFs) via exchange of molecular building blocks with different symmetries has been realized, which gives rise to the conversion between 2D COFs with distinct pore hierarchy.

scholarly journals Optoelectronic processes in covalent organic frameworks

2021 ◽  
Author(s):  
Niklas Keller ◽  
Thomas Bein
Keyword(s):  
Electron Transfer ◽  
Porous Materials ◽  
Building Blocks ◽  
Covalent Organic Frameworks ◽  
Molecular Building Blocks ◽  
Donor Acceptor

Covalent organic frameworks (COFs) are crystalline porous materials constructed from molecular building blocks using diverse linkage chemistries. The image illustrates electron transfer in a COF-based donor–acceptor system. Image by Nanosystems Initiative Munich.

A First Principles Approach for Partitioning Linear Response Properties into Additive and Cooperative Contributions

2018 ◽  
Author(s):  
Daniel Lambrecht ◽  
Eric Berquist
Keyword(s):  
First Principles ◽  
Linear Response ◽  
Building Blocks ◽  
Field Method ◽  
Response Property ◽  
Response Properties ◽  
Consistent Field ◽  
Molecular Building Blocks ◽  
Self Consistent ◽  
Self Consistent Field

We present a first principles approach for decomposing molecular linear response properties into orthogonal (additive) plus non-orthogonal/cooperative contributions. This approach enables one to 1) identify the contributions of molecular building blocks like functional groups or monomer units to a given response property and 2) quantify cooperativity between these contributions. In analogy to the self consistent field method for molecular interactions, SCF(MI), we term our approach LR(MI). The theory, implementation and pilot data are described in detail in the manuscript and supporting information.

Dibenzochrysene Enables Tightly Controlled Docking and Stabilizes Photoexcited States in Dual-Pore Covalent Organic Frameworks

2019 ◽  
Author(s):  
Torben Sick ◽  
Niklas Keller ◽  
Nicolai Bach ◽  
Andreas Koszalkowski ◽  
Julian Rotter ◽  
...  
Keyword(s):  
Molecular Docking ◽  
Photophysical Properties ◽  
Visible Spectrum ◽  
Large Family ◽  
Building Blocks ◽  
Band Gaps ◽  
Docking Site ◽  
Covalent Organic Frameworks ◽  
Connected Node ◽  
Optoelectronic Applications

Covalent organic frameworks (COFs), consisting of covalently connected organic building units, combine attractive features such as crystallinity, open porosity and widely tunable physical properties. For optoelectronic applications, the incorporation of heteroatoms into a 2D COF has the potential to yield desired photophysical properties such as lower band gaps, but can also cause lateral offsets of adjacent layers. Here, we introduce dibenzo[g,p]chrysene (DBC) as a novel building block for the synthesis of highly crystalline and porous 2D dual-pore COFs showing interesting properties for optoelectronic applications. The newly synthesized terephthalaldehyde (TA), biphenyl (Biph), and thienothiophene (TT) DBC-COFs combine conjugation in the a,b-plane with a tight packing of adjacent layers guided through the molecular DBC node serving a specific docking site for successive layers. The resulting DBC-COFs exhibit a hexagonal dual-pore kagome geometry, which is comparable to COFs containing another molecular docking site, namely 4,4′,4″,4‴-(ethylene-1,1,2,2-tetrayl)-tetraaniline (ETTA). In this context, the respective interlayer distances decrease from about 4.60 Å in ETTA-COFs to about 3.6 Å in DBC-COFs, leading to well-defined hexagonally faceted single crystals sized about 50-100 nm. The TT DBC-COFs feature broad light absorption covering large parts of the visible spectrum, while Biph DBC-COF shows extraordinary excited state lifetimes exceeding 10 ns. In combination with the large number of recently developed linear conjugated building blocks, the new DBC tetra-connected node is expected to enable the synthesis of a large family of strongly p-stacked, highly ordered 2D COFs with promising optoelectronic properties.

A new molecular building blocks: Synthesis, crystal structure, magnetic and spectroscopic properties of Cu(II) and Ni(II) macrocyclic complexes

Polyhedron ◽  
2011 ◽  
Vol 30 (15) ◽  
pp. 2550-2557 ◽  
Author(s):  
Katarzyna Suracka ◽  
Alina Bieńko ◽  
Jerzy Mroziński ◽  
Rafał Kruszyński ◽  
Dariusz Bieńko ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Building Blocks ◽  
Spectroscopic Properties ◽  
Macrocyclic Complexes ◽  
Molecular Building Blocks

scholarly journals Acid-Catalysed Liquid-to-Solid Transitioning of Arylazoisoxazole Photoswitches

2021 ◽  
Author(s):  
Luuk Kortekaas ◽  
Julian Simke ◽  
Niklas Arndt ◽  
Marcus Böckmann ◽  
Nikos Doltsinis ◽  
...  
Keyword(s):  
Building Blocks ◽  
Vital Role ◽  
Responsive Materials ◽  
Molecular Building Blocks ◽  
Physical Changes

Molecular photoswitches play a vital role in the development of responsive materials. These molecular building blocks are particularly attractive when multiple stimuli can be combined to bring about physical changes,...

A Molecular Artisans Guide to Supramolecular Coordination Complexes and Metal Organic Frameworks

2015 ◽  
Vol 03 (01n02) ◽  
pp. 1540004 ◽  
Author(s):  
Xialu Wu ◽  
David J. Young ◽  
T. S. Andy Hor
Keyword(s):  
Chemical Reactivity ◽  
Metal Organic Frameworks ◽  
Building Blocks ◽  
Coordination Complexes ◽  
Large Molecules ◽  
Molecular Building Blocks ◽  
Supramolecular Coordination ◽  
Metal Organic ◽  
Molecular Synthesis ◽  
And Function

As molecular synthesis advances, we are beginning to learn control of not only the chemical reactivity (and function) of molecules, but also of their interactions with other molecules. It is this basic idea that has led to the current explosion of supramolecular science and engineering. Parallel to this development, chemists have been actively pursuing the design of very large molecules using basic molecular building blocks. Herein, we review the general development of supramolecular chemistry and particularly of two new branches: supramolecular coordination complexes (SCCs) and metal organic frameworks (MOFs). These two fields are discussed in detail with typical examples to illustrate what is now possible and what challenges lie ahead for tomorrow's molecular artisans.

scholarly journals Inverse Design of Nanoporous Crystalline Reticular Materials with Deep Generative Models

2020 ◽  
Author(s):  
Zhenpeng Yao ◽  
Benjamin Sanchez-Lengeling ◽  
N. Scott Bobbitt ◽  
Benjamin J. Bucior ◽  
Sai Govind Hari Kumar ◽  
...  
Keyword(s):  
Self Assembly ◽  
Metal Organic Framework ◽  
Internal Surface ◽  
Building Blocks ◽  
Structural Features ◽  
Generative Models ◽  
Combinatorial Design ◽  
Surface Areas ◽  
Molecular Building Blocks ◽  
Metal Organic

Reticular frameworks are crystalline porous materials that form <i>via</i> the self-assembly of molecular building blocks (<i>i.e.</i>, nodes and linkers) in different topologies. Many of them have high internal surface areas and other desirable properties for gas storage, separation, and other applications. The notable variety of the possible building blocks and the diverse ways they can be assembled endow reticular frameworks with a near-infinite combinatorial design space, making reticular chemistry both promising and challenging for prospective materials design. Here, we propose an automated nanoporous materials discovery platform powered by a supramolecular variational autoencoder (SmVAE) for the generative design of reticular materials with desired functions. We demonstrate the automated design process with a class of metal-organic framework (MOF) structures and the goal of separating CO<sub>2</sub> from natural gas or flue gas. Our model exhibits high fidelity in capturing structural features and reconstructing MOF structures. We show that the autoencoder has a promising optimization capability when jointly trained with multiple top adsorbent candidates identified for superior gas separation. MOFs discovered here are strongly competitive against some of the best-performing MOFs/zeolites ever reported. This platform lays the groundwork for the design of reticular frameworks for desired applications.

scholarly journals Rearrangement of spiroderivatives of 1,3-benzo(naphtho)dioxin-4(1)-ones as a new method of synthesis of xanthene bromo derivatives

2021 ◽  
pp. 73-77
Author(s):  
A.V. Kovtun ◽  
◽  
S.A. Varenichenko ◽  
E.V. Zaliznaya ◽  
A.V. Mazepa ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
13C Nmr ◽  
Bromine Atom ◽  
Sodium Perchlorate ◽  
Building Blocks ◽  
Dimethylamino Group ◽  
1H And 13C Nmr ◽  
Molecular Building Blocks ◽  
Derivatives Of ◽  
Fold Excess

We have proposed a method for the synthesis of previously unknown bromo xanthenes using the reagent PBr3/DMF as a rearrangement initiator. Bromo derivatives of xanthenes in the form of organic perchlorates were prepared by reacting the corresponding benzo(naphtho)dioxin-4(1)-ones with a three-fold excess of Vilsmeier-Haack PBr3/DMF reagent at 1100C for 2 hours, followed by the addition of sodium perchlorate. The conditions for the synthesis of formyl derivatives of xanthenes under conditions of acid hydrolysis were selected. The structure of the compounds was confirmed by 1H and 13C NMR spectral data and mass spectrometry. Preliminary studies showed that it is possible to selectively replace the dimethylamino group and the bromine atom with various nucleophiles in bromo derivatives of xanthenes, which opens up wide possibilities for the synthesis of low-molecular building blocks and dyes.

scholarly journals Crystal structure of bacterial cytotoxic necrotizing factor CNF Y reveals molecular building blocks for intoxication

2021 ◽  
Author(s):  
Paweena Chaoprasid ◽  
Peer Lukat ◽  
Sabrina Mühlen ◽  
Thomas Heidler ◽  
Emerich‐Mihai Gazdag ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Building Blocks ◽  
Cytotoxic Necrotizing Factor ◽  
Molecular Building Blocks
Sign in / Sign up

Export Citation Format

Share Document