Search results for "RELIEF GRATINGS"

showing 4 items of 4 documents

Photoalignment and Surface-Relief-Grating Formation are Efficiently Combined in Low-Molecular-Weight Halogen-Bonded Complexes

2012

It is demonstrated that halogen bonding can be used to construct low-molecular-weight supramolecular complexes with unique light-responsive properties. In particular, halogen bonding drives the formation of a photoresponsive liquid-crystalline complex between a non-mesogenic halogen bond-donor molecule incorporating an azo group, and a non-mesogenic alkoxystilbazole moiety, acting as a halogen bond-acceptor. Upon irradiation with polarized light, the complex exhibits a high degree of photoinduced anisotropy (order parameter of molecular alignment > 0.5). Moreover, efficient photoinduced surface-relief-grating (SRG) formation occurs upon irradiation with a light interference pattern, with…

Materials scienceLightSurface Propertiesta221Supramolecular chemistryPhotochemistrysupramolecular complexeschemistry.chemical_compoundHalogensliquid crystalsLiquid crystalMaterials TestingMoietyMoleculeGeneral Materials Scienceliquid crystalta218Halogen bondta214Azobenzeneta114Mechanical Engineeringself-assemblyMolecular WeightRefractometryazobenzeneAzobenzenechemistryMechanics of Materialshalogen bondingHalogenazobenzene; halogen bonding; liquid crystals; self-assembly; supramolecular complexesSelf-assemblySettore CHIM/07 - Fondamenti Chimici Delle Tecnologiesurface relief gratings
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Supramolecular hierarchy among halogen and hydrogen bond donors in light-induced surface patterning

2015

Halogen bonding, a noncovalent interaction possessing several unique features compared to the more familiar hydrogen bonding, is emerging as a powerful tool in functional materials design. Herein, we unambiguously show that one of these characteristic features, namely high directionality, renders halogen bonding the interaction of choice when developing azobenzene-containing supramolecular polymers for light-induced surface patterning. The study is conducted by using an extensive library of azobenzene molecules that differ only in terms of the bond-donor unit. We introduce a new tetrafluorophenol-containing azobenzene photoswitch capable of forming strong hydrogen bonds, and show that an io…

RELIEF GRATINGSDENSITY-FUNCTIONAL THEORY CALCULATIONSMaterials sciencePHOTOINDUCED BIREFRINGENCE116 Chemical sciencesta221Supramolecular chemistryPhotochemistrysupramolecular chemistryDENSITY-FUNCTIONAL THEORYchemistry.chemical_compoundMaterials ChemistryMoleculeTHERMAL-ISOMERIZATIONPOLARIZATION DEPENDENCECO-CRYSTALSLIQUID-CRYSTAL ORDERta218chemistry.chemical_classificationta214Halogen bondta114PhotoswitchHydrogen bondPolymers Halogen Bonding Supramolecular Chemistry Photoresponsive AzobenzeneGeneral Chemistryhydrogen bondingPOLYMER-AZOBENZENE COMPLEXESSupramolecular polymersSOLID-STATEchemistryAzobenzeneHALOGEN BONDINGHalogenlight-induced surface patterningSettore CHIM/07 - Fondamenti Chimici Delle TecnologiePHOTONIC APPLICATIONSPOLYMER-AZOBENZENE COMPLEXES; DENSITY-FUNCTIONAL THEORY; LIQUID-CRYSTAL ORDER; RELIEF GRATINGS; SOLID-STATE; PHOTOINDUCED BIREFRINGENCE; POLARIZATION DEPENDENCE; THERMAL-ISOMERIZATION; PHOTONIC APPLICATIONS; CO-CRYSTALSJournal of Materials Chemistry C
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Optical Field-Induced Mass Transport in Soft Materials

2013

Abstract The dependence of the surface relief formation in amorphous chalcogenide (As 2 S 3 and As-S-Se) and Disperse Red 1 dye grafted polyurethane polymer films on the polarization state of holographic recording light beams was studied. It is shown that the direction of lateral mass transport on the film surface is determined by the direction of light electric vector and photoinduced anisotropy in the film. We propose a photoinduced dielectropfhoretic model to explain the photoinduced mass transport in amorphous films. Model is based on the photoinduced softening of the matrix, formation of defects with enhanced or decreased polarizability, and their drift under the electrical field gradi…

chemistry.chemical_classificationMaterials sciencebusiness.industryChalcogenideHolographic recordingPolymerOptical fieldSurface relief gratingsPhysics and Astronomy(all)Polarization (waves)Molecular physicsAmorphous solidchemistry.chemical_compoundCondensed Matter::Materials ScienceOpticschemistryAmorphous chalcogenide filmsAzo-dye polymersPolarizabilityCondensed Matter::SuperconductivityLight beambusinessAnisotropyPhysics Procedia
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Synthesis and Holographic Properties of Alkyl 2-Cyanoacetate Acceptor Fragment Containing Push – Pull Type Organic Glasses

2015

We present synthesis, optical and holographic properties of original structure organic glasses based on compounds consisting of three fragments: of N,N-bis(2-(trityloxy)ethyl)-4-vinylaniline or N,N-bis(5,5,5-triphenylpentyl)-4-vinylaniline fragments as electron donating fragment (D), 4H-pyran-4-ylidene fragment as linker(π) and of 2-(trityloxy)ethyl 2-cyanoacetate or 5,5,5-triphenylpentyl 2-cyanoacetate as acceptor (A) fragment. These push-pull (D- π-A) type molecular compounds show good solubility in non-polar solvents (CHCl3 or CH2Cl2) and neat thin films with sufficient optical qualities have been obtained by spin-coating technique. Maxima of UV–VIS absorption in dichloromethane solution…

organic glassesholographyluminophoresSurface relief gratingsalkyl 2-cyanoacetate darivatives
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