An assessment of the data processing and analysis methods used to obtain second- fourth-rank orientational order parameters liquid crystals from X-ray scattering experiments has been carried out, using experimental four extensively studied alkyl-cyanobiphenyls calculated generated two general types theoretical distribution function. The application a background subtraction different baseline correction profiles is assessed, along with three analyse processed data. choice method shown have...

Cinchona alkaloids have played an important part in the history of fluorescence studies and recent discovery their long-lived emission makes them a useful tool for exploring new applications labelling tagging. Furthermore, they are excellent model systems fundamental nature charge transfer due to through-space between nitrogen atom on cage quinoline aryl group. However, synthetic routes pathways modification cumbersome required. Here we demonstrate create wide range unnatural quinine...

Practical applications of guest-host liquid crystal systems are critically dependent on the alignment guest species within host. UV/Vis absorption spectroscopy shows that 1,5-dihydroxy-2,6-bis-(4-propylphenyl)-9,10-anthraquinone dye aligns E7 nematic host, giving an experimental dichroic ratio 9.40 and order parameter 0.74. This was modelled by using a combination density functional theory (DFT) molecular dynamics (MD) computational approaches do not require input data. Time-dependent DFT...

The optical properties of dyes dissolved in liquid crystals have led to their proposed use a diverse range practical applications. Such guest–host systems are typically required fulfil criteria relating absorption properties, degree alignment and stability, but concurrently satisfying these requirements has proven barrier widespread use. In this article, many the applications discussed, an outline some most prevalent classes dye context is given, along with summary recent reports that...

A set of experimental dichroic order parameters ranging from ca. +0.66 to -0.22 was obtained by recording polarized UV-visible absorption spectra aligned samples fifteen different guest anthraquinone and azo dyes in the nematic host 4-cyano-4'-pentylbiphenyl (5CB). DFT-optimised structures were calculated for between 1 16 conformers/tautomers each dye, their relative energies, wavelengths, oscillator strengths, transition dipole moments, molecular surface tensors quadrupole used subsequent...

A set of five anthraquinone dyes with bis(4-propylphenyl) substituent groups, connected via sulfide or amine linkages at the 1,5-positions directly 2,6-positions, have been studied in solution by UV–vis spectroscopy and electrochemistry, allied density functional theory calculations structures, electronic transitions, redox potentials. The visible transitions potentials are shown to vary HOMO LUMO energies, variation both color stability between being attributable principally variations...

Abstract The synthesis and evaluation of three novel bis‐1,2,4‐triazine ligands containing five‐membered aliphatic rings are reported. Compared to the more hydrophobic 1 – 3 six‐membered rings, distribution ratios for relevant f ‐block metal ions were approximately one order magnitude lower in each case. Ligand 10 showed an efficient, selective rapid separation Am III Cm from nitric acid. speciation with trivalent was probed using NMR titrations competition experiments, time‐resolved laser...

Analyses of MD simulations assess different definitions the axes along which molecules align in a nematic host, and effects molecular flexibility on transition dipole moment orientations.

Unprecedented Ir(<sc>iii</sc>) complexes of 5-(2-pyridyl)-1,2,4-triazine are described. The metal coordination drastically increases the speed Inverse Electron Demand Diels Alder reaction with strained bicyclooctyne BCN.

Coordination of Re( i ) to a 1,2,4-triazine ring speeds up the inverse electron demand Diels–Alder reaction with bicyclooctyne by factor 55. This coordination effect is more profound in 1,2,4-triazines than corresponding 1,2,4,5-tetrazines.

Five anthraquinone dyes with bis(4-propylphenyl) substituents, connected via sulfide or amine linking groups at the 1,5-positions directly 2,6-positions, have been studied as guests in nematic liquid crystal host, E7. Polarized UV-visible absorption spectra of aligned samples were used to obtain experimental dichroic order parameters, which exhibit values range 0.51-0.74. Fully atomistic MD simulations these guest-host systems carried out, generally using default parameters but new force...

Palladium-catalysed allylic amine rearrangements enable the ring expansion of 5- and 6-membered cyclic amines to their azepane azocane homologues. Reaction conditions are mild tolerate a range functionality, including aryl halides.

Temperature-dependent X-ray scattering studies have been carried out on 4-undecyloxy-4'-cyanobiphenyl (11OCB) and 4-(12,12-dimethyltridecyloxy)-4'-cyanobiphenyl (t-Bu-11OCB) in the smectic A phase, from which their layer spacings translational order parameters were obtained. Marked differences between structures of two compounds demonstrated, showing that addition t-Bu group results a higher parameter wider spacing for t-Bu-11OCB than 11OCB. Fully atomistic MD simulations both run >1000 ns...

Three 1,4-disubstituted anthraquinone dyes with bis(4-n-butylphenyl) substituents connected via amine or amide linking groups have been studied as guest molecules dissolved in the nematic host E7. UV-visible absorption spectroscopy has shown each of to exhibit multiple bands visible region, and dichroic order parameters obtained from polarised spectra aligned guest–host samples were differ significantly between for dye, dyes. Time-dependent density functional theory calculations indicated...

Photoswitches and dyes in the liquid-crystalline nematic phase have potential for use a wide range of applications. A large order parameter is desirable to maximize change properties induced by an external stimulus. set photochromic nonphotochromic were investigated these It was found that bent-shaped 7-substituted dihydroazulene (DHA) photoswitch exhibited properties. Further investigation demonstrated this material actually followed two distinct reaction pathways on heating, deactivated...

Atomistic molecular dynamics simulations of the ferroelectric liquid crystal 9HL replicate experimentally observed de Vries behaviour, which is shown to arise due differing tilting characteristics sub-units.

Phenanthroline-type ligand containing annealed 1,2,4-triazine ring was used to prepare novel Ir(III) complexes 3 and 4. The are non-luminescent but show luminogenic behaviour following inverse electron demand Diels-Alder (IEDDA) reaction with bicyclononyne (BCN) derivatives. It observed that the complex reacts BCN-C10 three times faster than corresponding free 7. magnitude of this accelerating metal-coordination effect, however, is less profound in previously reported 1,2,4-triazines which...

A phenanthroline-type ligand containing an annealed 1,2,4-triazine ring was used to prepare novel Ir(III) complexes 3 and 4. The are non-luminescent but show luminogenic behaviour following the inverse electron demand Diels-Alder (IEDDA) reaction with bicyclononyne (BCN) derivatives. It observed that react BCN-C10 faster than corresponding free ligands. magnitude of this accelerating metal-coordination effect, however, is less profound in previously reported 1,2,4-triazines, which triazine...

We have shown that palladium-catalyzed cascade processes provide modular access to rigid quinoline-containing tetracyclic amines. This approach enables fine-tuning of the through-space charge transfer (TSCT) state formation between lone pair localized on nitrogen atom in cage moiety and quinoline by variation both intramolecular N-aryl distance substitution. Decreasing this enhances TSCT species, giving control over emission color photoluminescence quantum yield. Methoxylation unit decreases...

Abstract Bis‐1,2,4‐triazine ligands are amongst the most promising soft N ‐donor for partitioning of trivalent actinides from lanthanides; a key separation proposed in future reprocessing spent nuclear fuels. In an effort to improve extraction properties these benchmark ligands, we propose herein general ligand design approach that is inspired by field drug discovery, and apply it new class which bidentate 3‐(2‐pyridyl)‐1,2,4‐triazine unit replaced 1,2,4‐triazine‐3‐carboxamide unit. A series...

Nanosegregating units are thought to promote de Vries behaviour, but simulations show consistency between mesogens with and without such units.

Despite their potential value within drug discovery, general methodologies enabling the two-carbon homologation of pyrrolidine and piperidine systems have yet to be developed. Herein we report that palladium-catalysed allylic amine rearrangements enable efficient ring expansion 2-vinyl piperidines azepane azocane counterparts. Conditions are mild, tolerant a range functional groups process can occur with high degree enantio-retention. The products formed undergo orthogonal transformations,...