Shift Of Absorption Edge Research Articles

Superior dielectric behaviour and band gap tuning of Zn doped MgO nanoparticles

ABSTRACT The primary aim was to study the doping effect of Zn in MgO nanoparticles (NPs) prepared by the co-precipitation method. X-ray diffraction (XRD) results inferred the cubic structure of MgO with good crystallinity, which changed with dopant additions. Scanning electron microscope (SEM) images exposed the development of NPs with decreasing size and dimensions with little agglomeration on doping. Fourier transform infrared (FTIR) results revealed the Mg-O bond formation, which is associated with Zn-O bond on increasing dopant content. UV Vis studies showed the red shift in absorption edge and decreased band gap with percentage of Zn dopant additions. The dielectric results exposed the dielectric constant, dielectric loss and ac conductivity of Zn-doped MgO NPs. Dopant addition led to the higher dielectric constant and low dielectric loss at lower frequency due to oxygen vacancies generation. The impedance behaviour in different frequency regimes illustrated the effective contribution of conductive grains and insulating grain boundaries.

Energy band reconstruction mechanism of Cl-doped Cu2O and photocatalytic degradation pathway for levofloxacin

Cl-doped Cu 2 O microparticles were prepared by hydrothermal synthesis . XRD, BET, SEM, TEM, UV–Vis and RSM were used to reveal the microstructure, optical properties and degradation regularity of the Cl-doped Cu 2 O microparticles. The band gap structures and state densities of Cl-doped Cu 2 O microparticles were computed based on density functional theory . The major intermediate degradation products and potential photocatalytic degradation pathways of levofloxacin were identified by HPLC–MS/MS. The photocatalytic active sites of levofloxacin and its intermediate products were calculated based on the frontier electron densities. The results showed that the prepared Cl-doped Cu 2 O microparticles increased the specific surface area and absorption efficiency of visible light compared with undoped pure Cu 2 O. The doping of Cl introduced hybrid orbitals and oxygen vacancy defects in the Cu 2 O crystal cell and decreased the forbidden bandwidth of Cu 2 O crystal microparticles, leading to a redshift of the absorption edge . Cl doping could form a shallow donor impurity energy level composed of Cl 3 p orbital in the energy gap of Cu 2 O and make the energy band denser and move to a lower energy, which could promote the electron leap to the conduction band through the impurity level . The doping of Cl can make the density of states curve of the Cu 2 O crystal shift to low-energy and the Cl-doped Cu 2 O rendered to half-metallic behavior and characteristic behavior of an n type semiconductor. The photocatalytic degradation of levofloxacin was attributed to attack of photogenerated holes and hydroxyl radicals , and the ring opening of the piperazine ring by oxidation and decarboxylation reactions from the quinolone ring might be two photocatalytic degradation pathways. This study revealed the mechanism of oxygen vacancy formation and the change rules of the band structure by doping of the nonmetal chlorine into Cu 2 O crystallites . • Migration laws of band structure and state density of Cl-doped Cu 2 O were revealed. • Doping of Cl introduced hybrid orbitals and oxygen vacancies in the Cu 2 O crystal. • Doping of Cl decreased band gap of Cu 2 O and led to red shift of absorption edge. • Holes and hydroxyl radicals are the main photocatalytic active species. • Degradation paths of levofloxacin were piperazine ring opening and decarboxylation.

Enhanced Photocatalytic Degradation of Rhodamine-B under Led Light Using CuZnAl Hydrotalcite Synthesized by Co-Precipitation Technique

The co-precipitation method was employed to synthesize a set of ZnAl hydrotalcite materials modified by Cu2+. The synthesized materials have a similar lamellar structure to that of hydrotalcite. The distance between layers is in the range of 7.73–8.56 Å. The network parameters a and c ranged from 3.058 to 3.074 Å and from 23.01 to 24.44, respectively. According to the IUPAC classification, the composites possess a mesoporous structure which belongs to class IV, type H 3. Particularly, the absorption edge shifts strongly to the visible light region when increasing the molar ratio of Cu2+ in the samples from 0 to 3.5. The photocatalytic activity of the synthetic materials was evaluated through the degradation efficiency of rhodamine-B (Rh-B) in the water and colorants in textile wastewater. The present study was the first to synthesize a material sample that contains a molar ratio of Cu2+ in the range of 2.5–3.5 and has high catalytic activities. They were able to degrade Rh-B at a high concentration (100 ppm) with a conversion rate of approximately 90% after 240 min of irradiation using a 30 W LED light. The catalytic activity of the composites depends on the molar ratio of modified Cu2+, the value of environmental pH, the H2O2 concentration and the irradiation time.

Influence of Ni doping on the structural and third order nonlinear optical properties of ZnMoO4 nanostructures

We report the third order nonlinear optical properties of Ni doped ZnMoO4 nanostructures with various concentration of Ni. The structural, optical and morphological properties have been investigated. X-ray diffraction pattern confirmed the successful incorporation of Ni into ZnMoO4 lattice without any secondary phase formation. The optical absorption spectra revealed a slight shift of absorption edge towards longer wavelength with an additional band appeared at 440 nm upon Ni doping. The variation of nonlinear optical properties of the synthesized nanostructures under continuous wave laser was investigated by a Z-scan technique at 532 nm. Experimental results reveal that the nanostructures exhibit reverse saturable absorption and negative nonlinearities. The measured third order nonlinear optical susceptibility was found to be in the order of 10−6 esu. Based on the observed results it is suggested that the nonlinear optical characteristics of the nanostructures could be controlled by Ni doping making them a potential candidate for optical device applications.

The effect of Ge addition on the optical and physical properties of thermally evaporated amorphous Pb15Se85-xGex (x = 0, 3, 6, 9, 12) thin films and bulk glasses

The effects of the addition of Ge on the optical and physical properties of a-Pb15Se85-xGex (x = 0, 3, 6, 9, 12 at. %) vacuum evaporated thin films are discussed in the given paper. An X-ray diffraction analysis of the films reveals no sharp peaks, indicating their amorphous nature. Transmission spectra of normal incidence were measured in the spectral window of 500 nm–2400 nm. An absorption edge shift has been observed with the addition of Ge at the expense of Se. Swanepoel analysis was applied to compute the refractive index values. Absorption losses were also calculated and discussed. The increase in Ge addition changes the refractive index and absorption coefficient. The bandgap transition is indirect and experimentally calculated using the Tauc-extrapolation method. Penetration depth and optical density were also calculated. WDD model was applied and static refractive index and WDD parameters were evaluated. Theoretical parameters viz. Cohesive energy, average heat of atomization, compactness, polaron radius were also calculated. Efforts were made to correlate obtained optical and physical parameters of the system.

Ni doping effect on the electronic, structural and optical properties of ZnO nanoparticles prepared by Co-precipitation route

Nanoparticles (NPs) synthesized by the co-precipitation technique show many attractive properties such as small particle size, high crystallinity, high average pore diameter and high specific surface area. However, numerous reports show that some characteristics of the Ni-doped ZnO (NZO) NPs remain controversial such as optical bandgap (Eg), surface morphology and defect level. In this study, pure ZnO and NZO NPs at different Ni contents (x) were successfully prepared using the co-precipitation method. Phase analysis confirms the hexagonal wurtzite crystallinity of the samples. XRD peak shows that the Ni may substituted ZnO structure as the peaks shift toward higher angles with increasing x. Meanwhile, the formation of NiO secondary phases was significant at 12.50% Ni content. Densely packed spherical shaped structures with nanoparticle agglomeration are observed at low x, while some nanorod shaped structures appear at higher x. The stretching vibrations of the Zn–O bond are observed in the NZO NPs. The absorption edge shifts to higher wavelengths with the increase in x. This study provides consistent results in the phase analysis, morphology and structural parameters. The decrease in Eg agrees with the photoluminescence measurements. The emission spectra confirm the presence of interstitial zinc and singly ionized oxygen vacancies.

Dynamical polarization, optical conductivity and plasmon mode of a linear triple component fermionic system

We investigate the density and optical responses of a linear triple component fermionic system in both non-interacting and interacting regimes by computing its dynamical polarization function, random phase approximation dielectric function, plasmon mode and long wavelength optical conductivity and compare the results with those of Weyl fermions and three-dimensional free electron gas. Linear triple component fermions are pseudospin-1 generalization of Weyl fermions, consisting of two linearly dispersive bands and a flat band. The presence of flat band brings about notable modifications in the response properties with respect to Weyl fermions such as induction of a new region in the particle–hole continuum, increased static polarization, reduced plasmon gap, shift in absorption edge, enhanced rate of increase in energy absorption with frequency and highly suppressed intercone transitions in the long wavelength limit. The plasmon dispersion follows the usual ω ∼ ω 0 + ω 1 q 2 nature as observed in other three-dimensional systems.

Ascendancy of Cr3+ on Cr6+ valence state and its effect on borate glass environment through CdO doping

Chromium borate glass has a stoichiometric composition of [0.3 Cr2O3-(80 – x) B2O3-19.7 Li2O-x CdO]; x = 0, 10, 20, 30, and 40 (mol. %) is amongst one of the most promising glass compositions for the optics realm being exhibits distinguishable optical transitions in both visible and ultraviolet regions. Glass materials are usually characterized by a set of experimentally techniques. Here, we exploit optical absorption, electron spin resonance, FT-IR, density, XRD, and EDX as distinct techniques to scrutinize the structural/optical properties of such glasses. Novelty, presented here, allowed to unequivocal recognize the high energy transition band of Cr6+ iõ ns (∼345 nm) by detaching this near edge optical transition that is mostly equivocal in borate glasses behind the bulk absorption edge. The amorphicity of all CdO-doped samples was scrutinized via x-ray diffraction, while the chemical composition was confirmed by EDX. The CdO doping reflects a considerable effect on the density and its related parameters. A quantitative analysis of FT-IR revealed the basic functional groups and determined both NBO and N4 ratios. These ratios related to the modifications in the essential units induced by Cd2+ ions. All-optical spectra of CdO-doped glass samples were normalized and deconvoluted. The prevailed feature is a manifestation of high energy transition band of Cr6+, with harshly increased in the conversion from Cr6+ to Cr3+. The physical characteristics of such band (e.g., position, intensity, …, etc) were aimly tuned through CdO doping. Other findings such as a large red shift of absorption edge (292–350 nm), narrow band gap (3.20–2.28 eV), disorderly effect (0.47–0.63 eV), and ligand field parameters (10 Dq, B, and C) were precisely determined. Slater-Condon parameters recalled the ligand field parameters to express the covalency effects. ESR data were congruous with the optical findings, manifesting the presence of resonance signals for Cr6+ and Cr3+. The present CdO-doped glasses suggest narrow band gap materials with optically active high energy transitions suitable for ultraviolet optics applications such as UV-black and white imaging, UV-forensic photography, and insect light traps.

Reduced recombination through CZTS/CdS interface engineering in monograin layer solar cells

The power conversion efficiency of Cu2ZnSnS4 (CZTS) solar cells is still limited by deep defects, low minority carrier lifetime and high recombination rates at the CZTS/CdS interface. The objective of this study was to find an effective method to reduce interface recombination of CZTS monograin layer solar cells. A two-step heterojunction formation process was applied by controlling the intermixing of Cd and Cu in the CZTS/CdS interface, which resulted in improved device efficiency of up to 11.7%. Surface analysis by x-ray photoelectron spectroscopy confirmed Cd diffusion into the surface of CZTS after CdS air-annealing by forming an ultra-thin Cu2Zn x Cd1−x SnS4 layer. Moreover, external quantum efficiency measurements showed that the absorption edge shifts to longer wavelengths with the addition of Cd into the CZTS surface layer. This surface modification and replacement of a CdS:Cu buffer layer by fresh CdS greatly reduced the interface recombination and improved the junction quality, contributing to an enhancement of J SC ∼3 mA cm−2 (from 20.5 to 23.6 mA cm−2) and fill factor ∼14% (from 59.4% to 67.7%). The serial resistance of the CZTS monograin layer solar cells was significantly reduced from 2.4 Ω cm2 to 0.67 Ω cm2. To understand the electrical behavior of the highest-efficiency CZTS monograin layer solar cell in more detail, the temperature-dependent current–voltage characteristics were analyzed.

Coconut Fiber Decorated with Bismuth Vanadate for Enhanced Photocatalytic Activity.

Bismuth vanadate/coconut fiber (BiVO4/CF) composites were synthesized by coprecipitation and calcination methods. All catalysts used in this work were prepared by a simple coprecipitation method and fully characterized by means of XRD, SEM-EDS, PL, BET N2 adsorption, zeta potential, and UV–vis DRS. Degradation of indigo carmine (IC) under visible light irradiation was tracked by the UV–vis technique. It was documented that XRD patterns of BiVO4 and BiVO4/CF samples retained the monoclinic structure. From SEM, the CF sheets were visualized, covering the surface of BiVO4 particles. The specific surface area of the synthesized catalysts increased from 1.77 to 24.82 m2/g. The shift of absorption edge to a longer wavelength corresponded to a decrease in band gap energy from 2.3 to 2.2 eV. The photocatalytic degradation rate of the BiVO4/CF composite was five times higher than that of pristine BiVO4. Moreover, the photocatalyst can be separated and recycled with little change after the third times recycling. The improved activity of the composite resulted from the combination of the adsorption performance of the substrate CF and the photocatalytic activity of BiVO4. In addition, the position of the specific mechanism could occur via both the active species of superoxide radical and hydroxyl radical.

Optical, Structural, and Mechanical Properties of Gd3Ga5O12 Single Crystals Irradiated with 84Kr+ Ions

Herein, the optical absorption, X‐ray diffraction (XRD) analysis data, and mechanical properties along the ion path are analyzed for gadolinium gallium garnet (Gd3Ga5O12 or GGG) single crystals irradiated with fast 84Kr ions to fluences of 1013–1014 ion cm−2. It is found that the optical absorption spectra of Czochralski‐grown unirradiated GGG crystal consist of relatively narrow lines in the UV spectral range associated with the 4f–4f transitions in Gd3+ ions. Transitions from the 6S7/2 ground state to the 6P, 6J, and 6D states in the Gd3+ cation are visible. An additional absorption band is also observed at 350 nm, which is associated with an uncontrolled Ca impurity. In irradiated GGG single crystals, a shift of the fundamental absorption edge by ≈30 nm to the long‐wavelength part of the spectrum is observed. The observed changes are caused by structural disturbances caused by depletion of the surface layer and an increase in the number of displaced atoms accompanied by an increase in the crystal lattice parameter. XRD analysis shows the presence of size effects and deformation of interplanar distances due to the displacement of atoms from the sites of the crystal lattice with subsequent migration. Hardness measurements show ion‐induced softening, which may be due to ion‐induced amorphization.

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The paper presents the transmission spectra of hybrid perovskite MAPbI3 single crystals near the fundamental absorption edge in a wide temperature range. The absorption coefficient α of the single crystal samples is estimated at a temperature T = 150 K for the light with a photon energy E = 1.6 eV and at T = 40 K for E = 1.8 eV. The obtained values turned out to be several orders of magnitude smaller than the values of α for thin-film samples known from the literature. A sharp shift of the fundamental absorption edge by ~ 100 meV was observed at a temperature T1 = 160 K of the structural phase transition from the tetragonal to the orthorhombic phase. The temperature hysteresis of the shift of the fundamental absorption edge near T1 was recorded, which is characteristic of a first-order phase transition.

Спектры пропускания монокристаллов гибридных перовскитов MAPbI-=SUB=-3-=/SUB=- вблизи края фундаментального поглощения

The paper presents the transmission spectra of hybrid perovskite MAPbI3 single crystals near the fundamental absorption edge in a wide temperature range. The absorption coefficient α of the single crystal samples is estimated at a temperature T = 150 K for the light with a photon energy E = 1.6 eV and at T = 40 K for E = 1.8 eV. The obtained values turned out to be several orders of magnitude smaller than the values of α for thin-film samples known from the literature. A sharp shift of the fundamental absorption edge by ~ 100 meV was observed at a temperature T1 = 160 K of the structural phase transition from the tetragonal to the orthorhombic phase. The temperature hysteresis of the shift of the fundamental absorption edge near T1 was recorded, which is characteristic of a first-order phase transition.

Nonlinear optical behaviour in amorphous GeSeSb thin films

In this paper we report nonlinear saturable absorption (SA) and other linear optical properties of amorphous chalcogenide- GeSeSb thin films. Chalcogenide glasses (chgs) are well known to possess large optical nonlinearity, high refractive index, wide infrared transparency etc. Here we have fabricated uniform thin films of different thickness from bulk GeSeSb glass via thermal evaporation method. Absorption and transmission measurements were done using UV–VIS-NIR spectrophotometer. A shift in absorption edge to higher wavelength with increase in film thickness has been observed. Linear refractive index was calculated by Swanepoel’s method and non linear studies were conducted by z-scan analysis. From this study we have found that these thin films are good saturable absorbers (SA). Our previous observations have confirmed that solution processed chalcogenide glasses shows reverse saturable absorption (RSA) properties, which increases with solute concentration. Collating both results we could infer that while moving from chalcogenide glass nanocolloids to chalcogenide glass thin films, these materials shows RSA to SA switching. High refractive index and high optical nonlinearity of chalcogenide glasses pave way for optical wave guides and logic gates applications.

First-principles study of transition metal atoms <i>X</i> (<i>X</i> = Mn, Tc, Re) doped two-dimensional WS<sub>2</sub> materials

Spintronics is a particularly hot topic in recent years, which has aroused much attention. The spin freedom of electrons can be used to construct logic devices and memory devices. Generally, the most important spintronic properties are found in half-metal ferromagnets, which are considered as the ideal materials for building spintronic devices due to their ability to provide fully spin-polarised conduction electrons. Numerous experimental data and theoretical studies have confirmed that the intercalation, doping and adsorption of transition metal atoms can induce magnetic properties in two-dimensional WS<sub>2</sub> material. Therefore, half-metal ferromagnets formed by doping WS<sub>2</sub> play an important role in the field of spintronics. In this paper, we investigate the electronic structure, magnetic and optical properties of the WS<sub>2</sub> doped with transition metal atoms <i>X</i> (<i>X</i> = Mn, Tc, Re) by the first-principles plane wave method based on density functional theory. The results show that the WS<sub>2</sub> system doped with transition metal atoms <i>X</i> is more stable under S-rich condition than under W-rich condition. Especially, the WS<sub>2</sub> system doped with Tc has a minimum value of formation energy of –1.292 eV under S-rich condition. After doping with Mn, impurity levels appear in the spin-up channels, resulting in the WS<sub>2</sub> system changing from a non-magnetic semiconductor to half-metal ferromagnet with a magnetic moment of 1.001 <inline-formula><tex-math id="M2">\begin{document}$ {\text{μ}}_{\text{B}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20212439_M2.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="12-20212439_M2.png"/></alternatives></inline-formula>. Moreover, in the Mn-doped system, the densities of states are asymmetric in the spin-up channel and the spin-down channel. After being doped with Tc and Re, the systems are transformed into non-magnetic N-type semiconductors, and the densities of states in spin-up and spin-down channels are symmetric in Tc doping system and Re doping system. Whereafter, the spin orbit splitting of the impurity states near the Fermi level <i>E</i><sub>F</sub> decreases successively from Mn to Re doped WS<sub>2</sub> systems. Compared with the undoped two-dimensional WS<sub>2</sub>, the transition metal atoms <i>X</i> doped WS<sub>2</sub> systems show that all doped systems not only have a significant red shift of optical absorption edges but also enhance peak value in infrared and visible light region, implying that the transition metal atoms <i>X</i> doped WS<sub>2</sub> systems have great application prospects in infrared and visible light detection. We hope that thepresent study of two-dimensional WS<sub>2</sub> will provide useful theoretical guidance for future experiments to explore low-dimensional spintronic materials.

Analysis of the effect of copper concentration on the structural, spectroscopic, and electrical properties of Cu:ZnO thin films

A detailed report on the investigation of structural, spectroscopic, and electrical properties of copper doped zinc oxide (CZO) thin films on the glass substrate is presented here. The spray pyrolysis technique was employed to prepare optimized ZnO thin films and copper (Cu) was added as the dopant with different concentrations. Structural properties of all samples were studied by analyzing the x-ray diffractogram (XRD) that showed a crystallite size around 40 nm. Zinc oxide (ZnO) films deposited at various Cu concentrations possess hexagonal crystal structure with (002) preferential orientation. At high copper concentrations, impurity peaks corresponding to copper were observed. Scanning electron micrographs (SEM) revealed good connectivity between the grains, along with the dense and uniform texturing on the surface. Absorbance spectra showed a red shift in absorption edge. A second band gap was observed at higher copper concentrations corresponding to the copper oxide (CuO) phase. Raman analysis with spatial imaging, x-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) studies were carried out for all the samples, that showed the presence of copper secondary phase at high copper concentration. CZO films showed higher resistivity than pristine ZnO. However, resistivity decreased at a higher Cu level. Photosensitivity measurements showed a sensitivity of about 32.64 for 5 at% Cu doped ZnO films under white light. Photosensitivity of the material is attributed to the copper-related defect levels.

Photo-induced solid-state reaction on the interface of As2S3–Ge30Se70 thin films

The laser-induced solid-state reaction in double-layer As2S3 and Ge30Se70 thin films evaporated on each other on substrates was studied. The extent of the solid-state reaction on the interface of two films was evaluated as a shift of the short-wavelength absorption edge, which was significantly higher for the illuminated/annealed double-layer in comparison with the sum of shifts of the individual virgin films. The presence of a newly created intermix layer was proved by FTIR, AFM and ellipsometry.

Synthesis, characterization, and photocatalytic performance of Cu/Y co-doped TiO2 nanoparticles

Cu and Y co-doped TiO2 nanoparticles were prepared with an acid-catalytic sol-gel process. XRD and Raman spectroscopy confirm the single anatase phase in all samples with a reduced crystallite size upon doping. SEM observations reveal uniform nanospheres (20–40 nm) being synthesised under the proposed processing conditions. The absorption edge shifts to the visible light region, as indicated by bandgap energy reduction. XPS results demonstrate that the Cu and Y dopants exist in the state of Cu+ and Y3+ ions, respectively. The dopant elements might have been doped into TiO2 lattice by substituting Ti4+ and generating oxygen vacancies for charge compensation. The photoactivity of the Cu/Y co-doped TiO2 is better than that of the undoped one, with the optimum doping concentration being 1.0 mol%. The improved photocatalytic performance is attributed to the effective separation of photon-generated electron-hole pairs, increased formation of active radicals, and increased surface area in the co-doped photocatalysts.

The effect of the thickness on structural, optical limiting, and dielectric properties of hybrid coatings rhodamine B dye films on an epoxy polymeric substrate for display applications

Various thickness of Rhodamine B (RhB) laser dye was deposited on epoxy polymeric as a new dielectric organic substrate by spin coating method for the first time. This study focused on the newly considered RhB dye on an epoxy substrate for wide-scale applications. The thickness effect on structural, optical, and dielectric properties of the hybrid coating films was performed. The XRD patterns of the films indicated a large hump amorphous design and lack of Bragg peak intensity associated with the RhB laser dye, due to amorphous film concentration. From UV-Visible spectroscopy, the optical absorption edge shifts to the higher wavelengths direction (redshift) with the variation in RhB dye thicknesses. It was found that the energy band gap decreased when the RhB dye film thickness changed. The refractive index is an important parameter influencing the optical component design. Their values vary according to each relationship that extremely useful the films in optical devices. Laser power attenuation sensitivity of pure epoxy polymeric substrate and its coating films shows that under reducing the thicknesses of RhB dye, the laser power intensity effect increases. Several dielectric parameters are extracted from the series and parallel capacitance measurements. The present results offer new material films for luminescent energy solar concentrator applications.

Application of the optical spectroscopy and X-ray diffraction methods for determining the effect of irradiation of the LR-115 type 2 track detector

The aim of this work is to evaluate the application of optical spectroscopy and X-ray diffraction methods as alternative methods for determining the dose dependence of the irradiation of solid-state nuclear track detectors (SSNTD) based on polymer films of nitrocellulose when irradiated with He particles. The choice of this type of film detectors as an object of research was due to its wide application for the detection of ionizing radiation during radionuclide decay. According to the data obtained, using optical analysis methods, it was found that an increase in exposure time leads to an increase in the transmission value and a shift in the fundamental absorption edge, which indicates the occurrence of changes in optical density in the material during accumulation of defects arising from the formation of latent tracks. The obtained data of structural changes using X-ray diffraction, showed that at small periods of exposure to ionizing radiation, the change of structural parameters is more severe than the change of optical characteristics. This is due to the fact that in the case of formation of single isolated tracks, the change in electron density along the trajectory of the ions is isolated and has a local character, while the change in structural characteristics, including the deformation is more pronounced. Such difference is also related to different mechanisms of energy losses of incident particles contributing to the change of structural and optical properties. Changing of optical properties is connected with electron losses of incident particles because the electron density changes as a result of particle passing along its trajectory, and this effect in case of single tracks is isolated and has a local character in a very small region. At the same time, the change of structural characteristics, in particular, deformations and displacements occur as a result of both elastic and non-elastic interactions of interacting particles with materials.