The photoluminescence kinetics of oligothiophene-phenylenesilane crystalline films

Poly- and single crystalline films of 5,5??-bis(4-trimethylsilylbenzene-1-yl)-2,2??-bithiophene were grown for the first time and their photoluminescent properties were studied. Single crystalline films show exponential photoluminescence kinetics with a lifetime of 0.97 ns. Polycrystalline films demonstrate more complex photoluminescence kinetics. The relationship between the film structure and the photoluminescence kinetics is discussed.     

Low-Frequency Raman Scattering of Transfer and Ribosomal RNA

JETP Letters - DNA and RNA are essential for the life of all organisms, as they support the storage and transfer of hereditary information and its use in protein construction. In addition, some...     

Laser hyperacoustic spectroscopy of single crystal germanium

Using a photothermal laser deflection technique the profiles of laser-induced hyperacoustic pulses in single crystal germanium were studied at a subnanosecond time resolution. It is shown that the hyperacoustic pulses are excited due to an electron-deformation interaction of photogenerated carriers with the crystal lattice, which is much more effective than the thermoelastic mechanism of the acoustic wave generation. Evolution of the hyperacoustic pulse profiles related to the diffraction and acoustic absorption effects was studied. An analysis of the hyperacoustic signal profiles allowed us to estimate the coefficient of ambipolar diffusion of the photogenerated charge carriers and the coefficient of hyperacoustic wave damping. It is established that the front of the electron-hole plasma laser-excited in germanium at room temperature propagates at a supersonic velocity.     

Modern photoelectric and photochemical methods of solar power conversion

A wider use of solar energy for electricity production and photocatalysis necessitates new efficient and low-cost materials. This paper reviews the principles of photoelectric solar power conversion and presents recent advances in the field of organic and hybrid solar cells: polymer-fullerene, polymer, low-molecular, dyesynthesized, etc. Approaches to enhancing the efficiency of organic solar cells are analyzed. Requirements for the development of new efficient materials for photovoltaics and photocatalysis are formulated. Examples of photocatalytic systems active under illumination with visible light are given.