V. Val. Sobolev

Electronic and crystal structures of isomorphic ZnP2 and CdP2

This paper reports on the results of precision investigations into the crystal structure of zinc diphosphide and cadmium diphosphide single crystals. The complete sets of fundamental optical functions are calculated for both crystals in the range 2.2–5.3 eV. The dielectric function is resolved into components for the first time. Three basic parameters of the oscillators are determined, and the electronic structures of ZnP2 and CdP2 are compared.

Optical spectra of six silicon phases

Spectra of the sets of fundamental optical functions were determined in the range of 2–5 eV at 295 K for six silicon phases: a single crystal, a porous silicon matrix, an amorphous film, microcrystalline films with and without hydrogen, and na-Si in a SiO2 matrix. Experimental permittivity spectra were used in the calculation. The main features of these spectra and dependences of energy of their structure on the nature of a silicon phase were established.

Chapter 5 – Optical Spectra of Arsenic Chalcogenides in a Wide Energy Range of Fundamental Absorption

This chapter presents new information on the spectra of complete sets of the fundamental optical functions of arsenic chalcogenide glasses in the range 0–35 eV, concerning their most intensive transitions and the main parameters of these transitions. Complete sets of the spectra of the fundamental optical functions of three glassy arsenic chalcogenides As 2 S 3 , As 2 Se 3 , As 2 Te 3 , and two phases of As x Se 1-x system in a wide energy range of intrinsic absorption are obtained. Their integral dielectric functions and characteristic bulk loss spectra are decomposed into the elementary transverse and longitudinal components. The main parameters of components are determined, including the transitions energies and probabilities. The schemes of interpretation of the components are proposed in the model of transitions occurring from the maximum densities of the occupied states to the unoccupied states. The obtained results substantially enlarge the amount of information about the optical spectra and electronic structure of As 2 X 3 glasses in a wide energy range of fundamental absorption. In addition, they lay a new principal foundation for the consideration of g-As 2 X 3 properties, and provide a basis for future theoretical calculations of their electronic structure and optical spectra.

Optical Properties and Electronic Structure of PdO

The complete set of optical spectra is calculated for the first time for crystalline PdO in the range 2–5.5 eV for the E ⊥ c and E || c polarizations using experimental dielectric permittivity data. The main features of the spectra are discussed. The origin of the strongest peaks in the spectra is inferred from comparison with band-structure calculations and polarized dielectric permittivity spectra.

Dielectric Permittivity of BiTeI

The dielectric permittivity and volume electron energy loss spectra of the ferroelectric semiconductor BiTeI are calculated for the E ⊥ c polarization in the range 0–12 eV. The spectra are decomposed into elementary components (13), and their principal parameters are evaluated. A correlation is found between the transverse and longitudinal components of interband transitions.

Optical Spectra of Palladium Oxide

The complete sets of spectra of the optical fundamental functions for porous films and single crystals of palladium oxide are determined in the range 1–6 eV. The main features of these functions and their dependences on the long-range order perfection of the structure are revealed.

Optical properties and electronic structure of fluorite and corundum

The complete sets of 12 fundamental optical functions for fluorite crystals in the range 5–39 eV and corundum crystals in the range 2–30 eV are determined from the experimental and theoretical spectra known for certain of these functions. The main features and generalities of these functions are revealed. A theoretical analysis of the optical spectra obtained is performed using the known theoretical band diagrams and the spectra of ɛ2.

Electron characteristic loss spectra of molybdenum dichalcogenides

The complete sets of the fundamental optical functions of molybdenum dichalcogenides have been considered for the first time. The energies of their bulk and surface plasmons of two types are determined. It is found that the energies of long-wavelength plasmons correlate with the energies of the deep minima in the reflectivity and ɛ2E2 spectra and the maxima in the reflectivity phase spectra.

Calculation of the Optical Spectra of Fluorite

Experimental, experimental–calculated, and theoretical absorption, reflection, and E2ε2(E) spectra of fluorite crystals were analyzed in the range 6–35 eV. General trends and characteristic features of the spectra were revealed, and the most reliable R(E) data were identified. The experimental–calculated α(E) and E2ε2(E) data were shown to agree well with predictions of two theoretical models.

Effect of spin-orbit interaction on the electronic structure of indium-antimonide d bands

The bands and densities of states of d bands in indium antimonide (InSb) are determined taking into account and disregarding the spin-orbit interaction. It is established that taking into account the effect of spin-orbit interaction results also in a substantial change in the dispersion of the obtained bands instead of only in the doublet splitting of the band of core d levels at ∼(0.79–0.86) eV. It is established that it is indium 4d states with eg and t2g symmetry that give the main contribution to the density of states. The calculations are carried out by the LAPW method with the exchange-correlation potential in the generalized gradient approximation (LAPW + GGA).