T HE DEVELOPMENT of modern bio-nanoelectronic technologies requires new hybrid organo-inorganic systems that have a specific functional purpose and allow work in the tissues of living organisms. The practical realization and scientific study of a hybrid twocomponent system in the form of DNA molecule fragments and nanoparticles of biocompatible ceramics was the goal of this work. The interaction of a DNA molecule with nanoparticles of a solid solution of the composition ZrO 2-3mol% Y 2 O 3 (YSZ) was studied using Raman scattering and transmission electron microscopy. Samples of YSZ oxide and hydroxide were investigated in triplicate at room temperature using LabRAM HR Evolution Horiba spectrometer and JEM 200A instrument. The effect of the force field of the surface of YSZ nanoparticles on the optical properties of the DNA molecule in the TRIS buffer solution was shown. The effects of increasing the intensity of spectral lines in the long-wavelength region 250-660 cm-1 (254 cm-1 , 322 cm-1 , 470 cm-1 , 663 cm-1). suppressing the intensity of spectral lines in the shortwave region 600-3300 cm-1 (604 cm-1 , 917 cm-1 , 951 cm-1 , 1256 cm-1 , 1302 cm-1 , 2767 cm-1 , 3180 cm-1 , 3241 cm-1 , 3285 cm-1), as well as shifting lines 519 cm-1 , 917 cm-1 , 1048 cm-1 , 1547 cm-1 and 1639 on 40-60 cm-1 in the shortwave region are established. From the standpoint of the theory of wave processes, a qualitative description of the detected Up-conversion effect was done. An assumption about the potential applicability of the YSZ nanoparticle surface-DNA nucleotide interfaces as a heterodyne frequency converter in molecular-and bio-electronic devices was made. Keywords: DNA in the electric field, immobilization of DNA molecules on the surface of semiconductors and dielectrics, Raman scattering, frequency modulation, heterodyne transfer of a frequency band, molecular electronics, bio-electronic, powder nanotechnologies.

The crystal structure, electronic and optical properties of lead-free mixed halide inorganic perovskites, CsSnI 3-x Br x (x = 0, 1, 2, 3), were studied within the framework of density functional theory. The effective electron-electron exchange correlation functional and, modified Becke-Johnson potential, were used for calculations of electronic and optical properties. The calculated optical parameters and the density of electronic states indicate that the CsSnI 3-x Br x system has a property favorable for application in solar cells.

In this work, to study the optical properties of orthorhombic perovskites of the CsSnBr3-xIx system, spin-orbital and spin-polarized quantum chemical calculations were carried out in the framework of the density functional theory. The effects of electron exchange correlation were taken into account by the modified Becke-Jones exchange-correlation potential (mBJ). It has been established that with an increase in the iodine concentration, the absorption capacity and photoconductivity of these semiconductors increase. Other optical properties were also calculated, such as the real and imaginary parts of the dielectric function, refractive indices, energy loss spectrum, extinction coefficients, and reflection coefficients. The high absorption of these compounds in the infrared, visible and ultraviolet energy ranges allows the use of these perovskites in optical and optoelectronic devices operating in all spectral ranges by controlling and changing their content. Doi: 10.28991/HEF-2021-02-04-08 Full Text: PDF

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In this study, by means of quantum-chemical calculations within the framework of density functional theory, we considered a number of structural and electronic properties of nanocrystals of the CsSn[Br1−xIx]3 (systems CsSnBr3, CsSnBr2I, CsSnBrI2 and CsSnI3) and discussed the effect of iodine concentration on the geometry and electronic properties of these materials. The exchange correlation effects of electrons were taken into account by the LDA, GGA and the modified Becke-Jones exchange correlation potential (mBJ). The results obtained in the framework of the DFT-mBJ and the Wien2k packages are in good agreement with the data from experimental measurements and open up the possibility of accurately predicting a number of fundamental properties of perovskite-like complex structures and the development of new materials. Doi: 10.28991/HIJ-2022-03-02-03 Full Text: PDF

In this work, using theoretical calculations within the framework of the density functional theory, taking into account the dispersive VDW interaction, the processes of adsorption and interaction of a water molecule with a TiO2 surface in various configurations are investigated. At the atomic / molecular level, the interactions of a water molecule with a TiO2 surface have been studied for various orientations. The results of calculations within the framework of DFT + VDW show that the adsorption energies of single water molecules in different initial positions on the substrate surface vary from -0.72 to -0.84 eV, and the most stable adsorbate structure is the TiO2 + H2O system upon adsorption of a molecule of water, parallel to the Y axis, because during the adsorption of H2O parallel to the Y axis, some favorable effects are observed in the band structure of titanium dioxide. On the one hand, the band gap decreases to 2.59 eV, and on the other hand, a new energy state appears in the band gap with an energy contribution of 0.17 eV, when water is physisorbed and interacts with a titanium atom at a distance of 2.12 Å and occupies a perpendicular position relative to the surface. Doi: 10.28991/HEF-2022-03-02-07 Full Text: PDF

T HIS work is aimed on a complex study of the DNA immobilization and conformation processes on the zirconium dioxide (ZrO 2) surface. The DNA+ZrO 2 nanoparticles and nanosized films were investigated with the molecular dynamics (MD) modeling, experimental spectral and integral methods, including nuclear physics. Using the MD hybrid classical and quantum chemistry potentials, for the DNA solvated with water the DNA+ZrO 2 surface interactions were simulated We have generated series MD models, thereby simulating a different scenario of the DNA with possible charge modifications. The DNA charge modification were introduced in the DNA central region via its two phosphorus atoms, P a and P b , and for several set of MD models for the relaxed DNA structures we have estimated the positional changes of the distance D[DNA(P a ,P b)-ZrO 2 (O)] between the phosphorus atoms (P a ,P b) and selected oxygen atoms of the ZrO 2 surface. The work is aimed to the development of functional heterojunctions such as a biological molecule-wide-gap dielectric. These heterojunctions are intended for useing in the field of molecular electronics, in particular, for the creation of biochips, memory arrays and computer architectures of the future.

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