Search

Your search keyword '"Purtov, Petr A."' showing total 8 results
Start Over Author "Purtov, Petr A."
8 results on '"Purtov, Petr A."'

1. Nonlocal tensor order parameter of the deformed state of liquid crystals

Author

Kudryavtsev, Alexey N., Purtov, Petr A., and Trashkeev, Sergey I.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

A generalized notion of a nonlocal tensor order parameter is introduced within the framework of the phenomenological approach. This parameter has the form of a traceless tensor correlation function or a tensor integral operator. Based on this form, the governing relations are written, which determine the steady states and phase transitions of the deformed liquid crystal. Linear relations for eigenfunctions of the introduced operator are derived. A principal drawback of currently available models of liquid crystals based on the local presentation of the tensor order parameter (equality of two Frank constants in the case of a quadratic form of the strain part of the free energy) is eliminated. Particular examples are considered, which demonstrate the model workability and the absence of contradictions in the model as well as its adequacy when describing small-scale structures., Comment: 29 pages, 4 figures, 46 references

Published
2017

3. Peculiarities of magnetic and spin effects in a biradical/stable radical complex (Three-Spin system): Theory and comparison with experiment

Author

Magin, Ilya M., Purtov, Petr A., Kruppa, Alexander I., and Leshina, Tatiana V.

Subjects
Density functionals -- Research, Magnetic fields -- Research, Chemical reactions -- Research, Chemicals, plastics and rubber industries
Abstract

The field dependencies of biradical recombination probability in the presence of paramagnetic species with spins S3=1 and S3=1/2 are calculated in the framework of the density matrix formalism. The spin exchange interaction between the added spin and one of the paramagnetic biradical centers are considered to describe the effect of the 'third' spin on the spin evaluation in biradical.

Published
2005

5. Reaction Operators for Radical Pairs. The Exactly Solvable Model.

Author

Purtov, Petr A.

Subjects
GEMINATE pairs (Molecules), CHARGE exchange, RECOMBINATION (Chemistry)
Abstract

In the present work, the reaction operator for radical pairs of the main equation of spin chemistry has been modified on the basis of an exactly solvable model. The model contains both the reversible and irreversible transitions. For this model, expression for the reaction operator is more complex due to the expanded basis of spin states. The reaction operator of a phenomenological equation is a particular case of a more general approach and only in the limiting case of the completely irreversible recombination process, these operators coincide. [ABSTRACT FROM AUTHOR]

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results