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Showing 1 to 20 of 25 for “"Chiroptical"”.
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Accurate Prediction of Chiroptical Properties
Accurate theoretical predictions of optical rotation are of substantial utility to the chemical community enabling the determination of absolute configuration without the need for poten- tially lengthy total synthesis. The requirements for robust calculation of gas-phase optical rotation are well …
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Photoresolvable compounds: Towards a chiroptical-liquid crystalline switch
… and a racemic state, this can be the basis for a chiroptical switch. Important parameters to control in the design of a photoresolvable compound are the optical properties that determine the degree of enantiomeric excess that one can attain at the photostationary state, the g value. Two strategies …
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Design and synthesis of suitable phototriggers for a chiroptical liquid crystal switch
… potential applications as phototriggers for a chiroptical liquid crystal switch were investigated via several approaches. Chiral exciton coupling theory was first used to design and synthesize a series of axially chiral arylmethylene cyclohexanes in both racemic and optically active forms for …
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Theoretical Simulations of Optical Rotation and Raman Optical Activity of Molecules in Solution
<p>Chiroptical spectroscopic techniques such as optical rotation (OR), electronic circular dichroism (ECD), and Raman optical activity (ROA) provide the means to probe molecular dissymmetry, which is the arrangement of atoms that is not superimposable on its mirror image. However, the application …
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Towards an Improved Method for the Prediction of Linear Response Properties of Small Organic Molecules
Quantum chemical methods to predict experimental chiroptical properties by solving the time-dependent Schrödinger equation are useful in the assignment of absolute configurations. Chiroptical properties, being very sensitive to the electronic structure of the system, require highly-accurate methods …
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A fiber optic polarimeter for use in chemical analysis
… field sensor applications and studies of chiroptical surface interactions.
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Optically active photoresponsive multifunctional polymeric materials
… on the effects induced on the thermal and chiroptical behaviours by the insertion of particulars achiral comonomers characterized by different side-chain mobility and grown hindrance (MMA, tert-BMA and TrMA). On the other hand carbazole containing polymers [2] have attracted much attention …
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Finite-Difference and Analytic-Gradient Approaches for Simulating Vibrational Circular Dichroism Using Second-Order Møller-Plesset Perturbation Theory and Configuration Interaction
… the effects of the choice of basis set on two chiroptical properties including VCD and Raman optical activity (ROA) with a particular emphasis on property-oriented basis sets. Next, we introduce a finite-difference scheme for computing the atomic axial tensor (AAT), a required quantity for VCD …
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Inducing Chirality in CdS Nanocrystals with Biomolecules
… like peptides and proteins, to generate chiroptical responses in these materials. Chapter 1 reviews the synthetic tunability of CdE NCs and current approaches of synthesizing chiral nanostructures. It then introduces the structural complexity of biomolecules and highlights existing …
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Probing light-matter interactions with differential polarizations: From chiral nanostructures to molecular sensing
… profoundly influences single-particle chiroptical measurements and must be considered in both interpretation and design of chiral plasmonic systems. Beyond intrinsic chirality, two-dimensional interfacial dichroism is studied in rotationally symmetric planar chiral pinwheels. Under …
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Sintesi e coordinazione di leganti Ciclopentadienilici O-Multifunzionalizzati
… of chiral tag, 1 exhibits solvent-dependent chiroptical properties (CD, αD^ 25), which are correlated to UV transitions and DFT calculations. The intra/inter molecular H-binding is crucial in driving the equilibrium between the observed atropisomers 1a and 1b, by varying the planar chirality …
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Optically Active Metamaterials Made of Plasmonic Nanoparticles and Chitin Nanocrystals
… resonance. Tuneable spectral features of such chiroptical properties were also realized, through the control of particle number density, size, and type. Possibilities of macroscopic optical activity arising from a seemingly completely disordered ensemble were assessed theoretically, with …
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Analysing Vibrational Circular Dichroism: Confidence Levels for Absolute Chirality Assignment
The application of chiroptical methods such as vibrational circular dichroism (VCD) spectroscopy is valuable in the assignment of absolute chirality. Assignment of chirality traditionally involves visual comparison of calculated and experimental spectra which can be subjective and time consuming. …
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Advanced Quantum Mechanical Simulations of Circular Dichroism Spectra
… whose stereochemical assignments and associated chiroptical properties can be incredibly sensitive to small changes in their three-dimensional structure, requiring highly accurate theoretical methods. On the other hand, due to the polynomial scaling with system size, it is sometimes impractical …
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In Pursuit of Extraordinarily Twisted Acenes
… racemic mixtures, the pure enantiomers display chiroptical properties, which make them interesting for study and potentially useful in materials applications. The deformation in these compounds is induced by the placement of bulky substituents at the peri positions of the acene, adjacent to one …
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Control of chiral optical and spin properties in low-dimensional perovskites
… lattice distortions, which underpin their strong chiroptical responses. Chiral optical properties are explored, with emphasis on the coupling of circularly polarized photoluminescence and second harmonic generation (SHG). Chiral perovskites exhibit SHG intensities an order of magnitude higher than …
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Higher kekulenes and Polymeric Helicenes
… catalysis, molecular actuators, conductive and chiroptical materials, we are interested in developing them in polymeric form. Ring closing metathesis (RCM) reaction was used to furnish the helicenes from a suitably designed polymer precursor, …
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Breaking Symmetry: A Study of Novel Phenomena in Asymmetric Nanoplasmonic Systems
… </p> <p>Part II of this work explores the chiroptical (CO) response of optical media. The potential several-orders of magnitude plasmonic enhancement of the weak circular dichroism (CD) response of natural molecules has generated a plethora of research interest and publications describing …
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Progress towards a highly efficient and accurate platform for enantiomeric excess determination
Enantiomeric excess (ee) determination remains as the bottleneck for high throughput screening of asymmetric catalysts. The work described herein sought to expand on two previously developed ee sensing assays from our lab– an iron based amine assembly and a zinc based multicomponent assembly. To …
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Molecular Encapsulation of Conjugated Polymers for Organic Electronics
… polymers, aiming to achieve a high degree of chiroptical properties. Specifically, the study centeres on [n]paracyclophane-based ([n]PC) conjugated polymers, designed to investigate various effects. These include altering the cyclophane chiral centre by changing the ansa unit, modifying the …
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