Elastic Flexibility in an Optically Active Naphthalidenimine-Based Single Crystal

Organic single crystals that combine mechanical flexibility and optical properties are important for developing flexible optical devices, but examples of such crystals remain scarce. Both mechanical flexibility and optical activity depend on the underlying crystal packing and the nature of the intermolecular interactions present in the solid state. Hence, both properties can be expected to be tunable by small chemical modifications to the organic molecule. By incorporating a chlorine atom, a reportedly mechanically flexible crystal of (E)-1-(4-bromo-phenyl)iminomethyl-2-hydroxyl-naphthalene (BPIN) produces (E)-1-(4-bromo-2-chloro-phenyl)iminomethyl-2-hydroxyl-naphthalene (BCPIN). BCPIN crystals show elastic bending similar to BPIN upon mechanical stress, but exhibit a remarkable difference in their optical properties as a result of the chemical modification to the backbone of the organic molecule. This work thus demonstrates that the optical properties and mechanical flexibility of molecular materials can, in principle, be tuned independently.

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The Influence of Nitrogen Position on Charge Carrier Mobility in Enantiopure Aza[6]helicene Crystals

10.26434/chemrxiv.7458719.v1 ◽

2018 ◽

Author(s):

Francesco Salerno ◽

Beth Rice ◽

Julia Schmidt ◽

Matthew J. Fuchter ◽

Jenny Nelson ◽

...

Keyword(s):

Solid State ◽

Charge Carrier ◽

Carrier Mobility ◽

Chemical Structure ◽

Crystal Packing ◽

Charge Carrier Mobility ◽

Individual Factor ◽

Charge Mobility ◽

Order Of Magnitude ◽

Small Change

<p>The properties of an organic semiconductor are dependent on both the chemical structure of the molecule involved, and how it is arranged in the solid-state. It is challenging to extract the influence of each individual factor, as small changes in the molecular structure often dramatically change the crystal packing and hence solid-state structure. Here, we use calculations to explore the influence of the nitrogen position on the charge mobility of a chiral organic molecule when the crystal packing is kept constant. The transfer integrals for a series of enantiopure aza[6]helicene crystals sharing the same packing were analysed in order to identify the best supramolecular motifs to promote charge carrier mobility. The regioisomers considered differ only in the positioning of the nitrogen atom in the aromatic scaffold. The simulations showed that even this small change in the chemical structure has a strong effect on the charge transport in the crystal, leading to differences in charge mobility of up to one order of magnitude. Some aza[6]helicene isomers that were packed interlocked with each other showed high HOMO-HOMO integrals (up to 70 meV), whilst molecules arranged with translational symmetry generally afforded the highest LUMO-LUMO integrals (40 - 70 meV). As many of the results are not intuitively obvious, a computational approach provides additional insight into the design of new semiconducting organic materials.</p>

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Quantum optics with nitrogen-vacancy centres in diamond

10.1093/oso/9780198768609.003.0005 ◽

2017 ◽

Cited By ~ 1

Author(s):

Yiwen Chu ◽

Mikhail D. Lukin

Keyword(s):

Optical Properties ◽

Quantum Information ◽

Solid State ◽

Quantum Optics ◽

Quantum States ◽

Nitrogen Vacancy ◽

Common Theme ◽

External Effects ◽

Promising Candidate ◽

Optical Photons

A common theme in the implementation of quantum technologies involves addressing the seemingly contradictory needs for controllability and isolation from external effects. Undesirable effects of the environment must be minimized, while at the same time techniques and tools must be developed that enable interaction with the system in a controllable and well-defined manner. This chapter addresses several aspects of this theme with regard to a particularly promising candidate for developing applications in both metrology and quantum information, namely the nitrogen-vacancy (NV) centre in diamond. The chapter describes how the quantum states of NV centres can be manipulated, probed, and efficiently coupled with optical photons. It also discusses ways of tackling the challenges of controlling the optical properties of these emitters inside a complex solid state environment.

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ChemInform Abstract: EFFECT OF CRYSTAL PACKING ON THE SOLID-STATE SPECTRAL PROPERTIES OF VICINAL DIKETONES

Chemischer Informationsdienst ◽

10.1002/chin.198404056 ◽

1984 ◽

Vol 15 (4) ◽

Author(s):

J. I. CROWLEY ◽

R. D. BALANSON ◽

J. J. MAYERLE

Keyword(s):

Solid State ◽

Spectral Properties ◽

Crystal Packing

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Synthesis of a New Series of Organic Solid-State Near-Infrared Emitters: The Role of Crystal Packing and Weak Intermolecular Interactions and Application in Latent Fingerprint Detection

Crystal Growth & Design ◽

10.1021/acs.cgd.0c01392 ◽

2021 ◽

Vol 21 (2) ◽

pp. 1062-1076

Author(s):

Ranjit Singh ◽

Abhishek Kumar Gupta ◽

Chullikkattil P. Pradeep

Keyword(s):

Solid State ◽

Intermolecular Interactions ◽

Near Infrared ◽

Crystal Packing ◽

Latent Fingerprint ◽

Weak Intermolecular Interactions ◽

Organic Solid ◽

Infrared Emitters ◽

Fingerprint Detection

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Thiophene-Based Trimers and Their Bioapplications: An Overview

Polymers ◽

10.3390/polym13121977 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1977

Author(s):

Lorenzo Vallan ◽

Emin Istif ◽

I. Jénnifer Gómez ◽

Nuria Alegret ◽

Daniele Mantione

Keyword(s):

Optical Properties ◽

Medical Research ◽

Turning Point ◽

State Of The Art ◽

Thiophene Ring ◽

Functional Polymers ◽

Direct Application ◽

Synthetic Methods ◽

Scientific Interest ◽

Chemical Modifications

Certainly, the success of polythiophenes is due in the first place to their outstanding electronic properties and superior processability. Nevertheless, there are additional reasons that contribute to arouse the scientific interest around these materials. Among these, the large variety of chemical modifications that is possible to perform on the thiophene ring is a precious aspect. In particular, a turning point was marked by the diffusion of synthetic strategies for the preparation of terthiophenes: the vast richness of approaches today available for the easy customization of these structures allows the finetuning of their chemical, physical, and optical properties. Therefore, terthiophene derivatives have become an extremely versatile class of compounds both for direct application or for the preparation of electronic functional polymers. Moreover, their biocompatibility and ease of functionalization make them appealing for biology and medical research, as it testifies to the blossoming of studies in these fields in which they are involved. It is thus with the willingness to guide the reader through all the possibilities offered by these structures that this review elucidates the synthetic methods and describes the full chemical variety of terthiophenes and their derivatives. In the final part, an in-depth presentation of their numerous bioapplications intends to provide a complete picture of the state of the art.

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Convenient Access to Functionalized Non-Symmetrical Atropisomeric 4,4′-Bipyridines

Compounds ◽

10.3390/compounds1020006 ◽

2021 ◽

Vol 1 (2) ◽

pp. 58-74

Author(s):

Emmanuel Aubert ◽

Emmanuel Wenger ◽

Paola Peluso ◽

Victor Mamane

Keyword(s):

Solid State ◽

Intermolecular Interactions ◽

Medicinal Chemistry ◽

Crystal Packing ◽

Cross Coupling ◽

Coupling Reactions ◽

Halogen Bonds ◽

Cross Coupling Reactions ◽

Cyano Groups ◽

Post Functionalization

Non-symmetrical chiral 4,4′-bipyridines have recently found interest in organocatalysis and medicinal chemistry. In this regard, the development of efficient methods for their synthesis is highly desirable. Herein, a series of non-symmetrical atropisomeric polyhalogenated 4,4′-bipyridines were prepared and further functionalized by using cross-coupling reactions. The desymmetrization step is based on the N-oxidation of one of the two pyridine rings of the 4,4′-bipyridine skeleton. The main advantage of this methodology is the possible post-functionalization of the pyridine N-oxide, allowing selective introduction of chlorine, bromine or cyano groups in 2- and 2′-postions of the chiral atropisomeric 4,4′-bipyridines. The crystal packing in the solid state of some newly prepared derivatives was analyzed and revealed the importance of halogen bonds in intermolecular interactions.

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Scalable Production of Boron Quantum Dots for Broadband Ultrafast Nonlinear Optical Performance

Nanomaterials ◽

10.3390/nano11030687 ◽

2021 ◽

Vol 11 (3) ◽

pp. 687

Author(s):

Shuolei Meng ◽

Qianyuan Chen ◽

Hongjian Lin ◽

Feng Zhou ◽

Youning Gong ◽

...

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Relaxation Time ◽

Nonlinear Optical ◽

Average Diameter ◽

Optical Devices ◽

Nonlinear Optical Properties ◽

Saturable Absorption ◽

Nonlinear Optical Susceptibility ◽

Tandem Structure

A simple and effective approach based on the liquid phase exfoliation (LPE) method has been put forward for synthesizing boron quantum dots (BQDs). By adjusting the interactions between bulk boron and various solvents, the average diameter of produced BQDs is about 7 nm. The nonlinear absorption (NLA) responses of as-prepared BQDs have been systematically studied at 515 nm and 1030 nm. Experimental results prove that BQDs possess broadband saturable absorption (SA) and good third-order nonlinear optical susceptibility, which are comparable to graphene. The fast relaxation time and slow relaxation time of BQDs at 515 nm and 1030 nm are about 0.394–5.34 ps and 4.45–115 ps, respectively. The significant ultrafast nonlinear optical properties can be used in optical devices. Here, we successfully demonstrate all-optical diode application based on BQDs/ReS2 tandem structure. The findings are essential for understanding the nonlinear optical properties in BQDs and open a new pathway for their applications in optical devices.

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Zn(II) Heteroleptic Halide Complexes with 2-Halopyridines: Features of Halogen Bonding in Solid State

Molecules ◽

10.3390/molecules26113393 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3393

Author(s):

Mikhail A. Vershinin ◽

Marianna I. Rakhmanova ◽

Alexander S. Novikov ◽

Maxim N. Sokolov ◽

Sergey A. Adonin

Keyword(s):

Solid State ◽

Quantum Yield ◽

Crystal Packing ◽

Halogen Bonding ◽

Molecular Complexes ◽

Substituted Pyridines ◽

Halide Complexes

Reactions between Zn(II) dihalides and 2-halogen-substituted pyridines 2-XPy result in a series of heteroleptic molecular complexes [(2-XPy)2ZnY2] (Y = Cl, X = Cl (1), Br (2), I (3); Y = Br, X = Cl (4), Br (5), I (6), Y = I, X = Cl (7), Br (8), and I (9)). Moreover, 1–7 are isostructural (triclinic), while 8 and 9 are monoclinic. In all cases, halogen bonding plays an important role in formation of crystal packing. Moreover, 1–9 demonstrate luminescence in asolid state; for the best emitting complexes, quantum yield (QY) exceeds 21%.

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