摘要:

The preparation conditions and the molecular structure of a composite material which consists of a bicopper complex encapsulated in a cylinder-like, polymer sheath are briefly described.

ISSN:1058-725X    

DOI:10.1080/10587259808047155

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The recently proposed nearest-neighbour model of the coupling between the Frenkel and charge transfer (CT) excitations of a molecular crystal, successfully applied for the calculation of the electroabsorption (EA) spectra of polyacenes and fullerene, is applied to probe the influence of different intramolecular excited states on the EA signal in the CT energy range. The study highlights the pre-eminent role of Frenkel excitons that are energetically close to the CT manifold, even if they are inactive in conventional absorption spectroscopy. The high-energy intense excitons are found to have a lesser effect. The study suggests EA spectroscopy as a potential tool to detect and locate some of the absorption-inactive intramolecular excitations.

ISSN:1058-725X    

DOI:10.1080/10587259808047156

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The results of the investigations of spectral properties and excitation energy transfer in π-electron-containing polymers carried out in Kyiv University are briefly reviewed. The peculiarities of fluorescence, delayed fluorescence, singlet and triplet exciton propagation, mechanisms of elementary acts of singlet and triplet energy transfer are examined and analyzed. Some proofs of vibrational excitons in π-electron-containing polymers are presented.

ISSN:1058-725X    

DOI:10.1080/10587259808047157

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The possibility of using the direct electronic excitation energy transfer for energy supply to definite points of molecular systems for initiation of the chemical reactions or, on the contrary, for drainage of electronic excitation energy from the points of molecular systems suitable for reactions with the aim of their stabilization is examined. An analysis of Fries photorearrangement process in investigated compounds confirms the possibility of affecting the rate of Fries photorearrangement by means of electronic excitation energy supply.

ISSN:1058-725X    

DOI:10.1080/10587259808047158

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Some variants of using the excitation energy transfer for the stabilization of polymers are examined. Intramolecular photostabilizers acting due to exciton trapping are proposed.

ISSN:1058-725X    

DOI:10.1080/10587259808047159

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Some models of macromolecular electronic systems, first steps in their creation and difficulties on the way of their design and synthesis were examined.

ISSN:1058-725X    

DOI:10.1080/10587259808047160

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Voltage-current characteristics are reported for several bioequivalent structures with liquid crystalline ordering. Measurements were carried out at different temperatures with or without irradiation by UV light. Three types of structures were studied: (1) a liquid crystalline mixture of Schiff bases (MBBA+EBBA), (2) a eutectic mixture of liquid crystalline cyanobiphenyls, and (3) non-saturated long chain carboxylic acids (e.g., oleic). For systems (1) and (2), characteristic local minima on current-temperature curves were observed, with corresponding temperatures decreasing at higher voltages. Tentative mechanisms are discussed in terms of thermoactivation of traps and liquid crystalline ordering. For systems (1) and (3), thermostimulated currents were clearly increased under the influence of UV-irradiation. This phenomenon was completely absent with system (2), which suggested a possibility of interpretation in terms of bioequivalence of liquid crystalline structures.

ISSN:1058-725X    

DOI:10.1080/10587259808047161

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Chiral dopants are optically active substances used in liquid crystal systems. We have investigated the helical twisting power and its temperature dependences for the systematic rows of optically active organic compounds synthesized on the base of 2-methylbutanol ande-menthol. The compounds differ by molecular, chemical and spatial structure. Correlation between the value of helical twisting power and molecular structure of chiral dopants is analyzed. The mesogenity of new chiral dopants is also discussed.

ISSN:1058-725X    

DOI:10.1080/10587259808047162

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Performances of new batteries and PEM Fuel Cells are tightly dependent on the organic materials, including solvents and plasticizers, salts, polymers and polyelectrolytes. The functional materials must provide high performance but their cost in the event of mass-production is also a key parameter. The paper deals with the organic materials involved in lithium batteries and PEMFC.

ISSN:1058-725X    

DOI:10.1080/10587259808047163

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The exciton trapping mechanism by impurity centers in quasi-1D molecular chains (J-aggregates) is studied for the binary solutions of dimethylformamide and water. It is determined that the exciton energy transfer is occurring due to the dipole-dipole mechanism. The influence of the exciton self-trapping process on the trapping efficiency was found. It is shown that the exciton trapping occurs mainly owing to free excitons. The critical radius and trapping rate were determined.

ISSN:1058-725X    

DOI:10.1080/10587259808047164

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor