The reaction between phenalenon derivatives containing hydroxy group in peri-position to carbonyl and propynol was studied. A new hybrid compound was synthesized, and its spectral-kinetic properties were measured. This compound has photochromic and fluorescent properties in one time.

A study was carried out and a comparative analysis of the spectral-kinetic (absorption and fluorescent) characteristics of nanospheres containing luminescent inorganic quantum dots (QDs) CdSe/ZnS, covered with an amphiphilic polymer shell, which ensures the stability of nanospheres in aqueous colloidal solutions and the possibility of introducing into them hydrophobic photochromic diarylethene molecules with different structure. Photoinduced reversible isomerization of diarylethene molecules causes modulation of the photoluminescence signal of quantum dots, including through the control of the efficiency of resonant energy transfer (FRET) from quantum dots to the cyclic isomer of diarylethene. The FRET efficiency turned out to be the highest in nanospheres with DAE2 and DAE4. The value of the quality index (QF) of the FRET photomodulator (which shows the efficiency of modulation of the quantum yield of QD photoluminescence), introduced in this work, varies for samples with different diarylethenes from 0.003 (for DAE1) to 0.09 (for DAE2). Nanospheres containing luminescent nanoparticles of various shapes can be used in the development of luminescent photocontrolled panels, fluorescent markers, etc.

An analysis of the results of complex experimental and theoretical studies of photoinduced changes in the spectral properties of photochromic diarylethene in various nanostructured systems is presented. The properties of diarylethene were studied in solutions in the presence of colloidal metal and semiconductor nanoparticles, as well as in the form of solid-phase composite nanostructured core-shell systems based on colloidal nanoparticles with a shell of diarylethene molecules (including in a polymer matrix). A photoinduced reversible change in the electronic and vibrational spectra of diarylethene in various studied matrices was found. The results can be used to create optoelectronic photo-switchable elements for ultra-high-capacity memory devices, photo-controlled molecular switches and sensors.

Photo-induced change of the electrical properties of diarylethenes in nanocomposites/ G.T. Vasilyuk [ и др.] // Book of abstracts : the 4th International symposium 'Molecular photonics' dedicated to academician A.N. Terenin, Peterhof, St. Petersburg, July 21-24, 2016.- Санкт-Петербург : [Б. и.], 2016 .- С.73 Статья

A method for the synthesis of polymer photochromic composites containing photochromic nitro-substituted spiropyran via mechanical mixing in melt is developed, and dependences of the spectral and kinetic properties of the samples on the nature of chosen thermoplastic polymer matrices (polyolefins, polycarbonate) and their processing temperatures are studied.

The results of the authors’ studies on development of a multilayer photochromic sun-protective energy-saving polymer film able of reversibly changing its light transmission depending on the intensity of the activating irradiation and of permanently reflecting thermal radiation were analyzed.

Methods of fabrication of solid-phase composite Ag- and Au-containing nanostructured systems with a shell of photochromic diarylethenes molecules (DAE) have been developed. The samples of nanocomposite systems were obtained. These nanocomposites exhibit photochromic properties similar to the properties of DAE in solution and solid-phase layers not containing metal nanoparticles. A chemical interaction between nanoparticles and sulfur-containing derivatives of DAE in solid-phase nanocomposites was detected.

A functionalization of the surface of detonation nanodiamonds by photochromic spirocompounds from the classes of spiropyrans and spirooxazines has been carried out for the first time. A comparative study of the interaction of nanodiamonds with positive and negative potential is performed by the spectral–kinetic method, which shows the possibility of surface modification by only functionalized molecules of spirocompounds with the formation of surface proton complexes. This is confirmed by the hypsochromic shift of the absorption bands of the photoinduced merocyanine forms of adsorbed molecules of spirocompounds and by the decrease of the speed of their dark relaxation to the initial state in the presence of nanodiamonds with a negative potential.

A novel hybrid compound composed of substituted imidazole and salicylideneaniline luminophors has been synthesized and shown to exhibit multiple luminescence in ethanol, which can be switched by varying the excitation wavelength.

Using the method of microsecond flash photolysis with UV and visible light, the spectral and kinetic characteristics of intermediate products of photolysis in toluene and methanol solutions of a new biphotochromic compound have been studied, in which two photochromic moieties, spironaphthoxazine and azomethine, are linked to each other in such a way that there is conjugation between π-electronic systems of the moieties in the ground state of the molecule. Two intermediate products have detected, whose relative efficiency of formation substantially depends on the solvent and the wavelength of excitation light.

Методом микросекундного импульсного фотолиза УФ и видимым светом в растворах толуола и метанола исследованы спектрально-кинетические характеристики промежуточных продуктов фотолиза нового фототрифункционального соединения (ФТС), молекула которого объединяет спиронафтооксазиновый, гидроксиазометиновый и азобензольный фрагменты. Зарегистрированы три продукта фотолиза ФТС. Установлено, что эффективность фотопроцессов существенно зависит от растворителя и длины волны возбуждающего света.

A comparative investigation of the photochromism of photochromic spiropyrans, spirooxazines, and diarylethenes in solutions and in solid-phase films in the absence and in the presence of silver and gold nanoparticles was undertaken by a kinetic spectral method. On the basis of the experimental data it was concluded that hybrid photochromic nanoparticles of the core–shell type can be obtained as a result of chemical reaction of functionalized molecules with the nanoparticles of noble metals.

Photochromic polymeric thin films have been prepared by vacuum co-deposition of polytetrafluoroethylene (PTFE) and thermally irreversible photochromic compounds: the cyclopentene derivative of diarylethene and fulgimide. Their photochromic properties were studied using the spectral-kinetic method as compared with polymethyl methacrylate (PMMA) films filled with the same photochromic compounds prepared using the spin coating method. The films prepared using co-deposition in vacuum are characterized by photochromic properties acceptable for recording media for 3D optical memory.

Photochromic polymer thin films have been prepared by vacuum co-deposition of PTFE and several spirocompounds. Their photochromic properties were studied with the use of the spectral-kinetic method. A number of positive properties for application of these films were found.

This paper presents latest own results in the development of reversible photochromic and irreversible photofluorescent polymer systems providing fabrication of multilayer recording media for 3D optical memory with super high information capacity. It was shown that synthesized thermal irreversible photochromic diarylethenes into plastic binders allow to prepare photochromic polymer layers providing nondestructive refractive read-out of optical information. These photochromic polymer layers were used for preparation of six-layer recording media tested with the positive results using the framed optical device. This device imitated layer-by-layer writing, erasure and read-out of optical signals. Experimental evidences for making photochromic polymer layers based on a mixture of photochromic diarylethene and dye — phosphor with nondestructive fluorescent read-out are presented too. Polymer systems based on light-sensitive chromones manifest an irreversible photochemical transformations of these non-fluorescing compounds into the fluorescent products under UV irradiation. Received results open perspectives for making multilayer optical discs for bitwise working (based on photochromic systems) and archival (based on irreversible photofluorescent systems) optical memory with information capacity more 1 TB.

This paper presents latest own results in the development of reversible photochromic and irreversible photofluorescent polymer systems providing fabrication of multilayer recording media for 3D optical memory with super high information capacity. It was shown that synthesized thermal irreversible photochromic diarylethenes into plastic binders allow to prepare photochromic polymer layers providing nondestructive refractive read-out of optical information. These photochromic polymer layers were used for preparation of six-layer recording media tested with the positive results using the framed optical device. This device imitated layer-by-layer writing, erasure and read-out of optical signals. Experimental evidences for making photochromic polymer layers based on a mixture of photochromic diarylethene and dye - phosphor with nondestructive fluorescent read-out are presented too. Polymer systems based on light-sensitive chromones manifest an irreversible photochemical transformations of these non-fluorescing compounds into the fluorescent products under UV irradiation. Received results open perspectives for making multilayer optical discs for bitwise working (based on photochromic systems) and archival (based on irreversible photofluorescent systems) optical memory with information capacity more 1 TB.