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Phase transformations of SiC crystals with grown original defects and thin films have been presented. The SiC crystals were grown by the Tairov method and the films were obtained by the “sandwich” and Chemical Vapor Deposition (CVD) methods. The analysis of absorption spectra, excitation spectra and low-temperature photoluminescence spectra testifies to the formation of a new microphase during the growth. The complex spectrum can be decomposed into similar structure-constituting spectra shifted on the energy scale relative to the former. Such spectra are indicators of the formation of new nanophases. The joint consideration of photoluminescence spectra, excitement photoluminescence spectra and absorption spectra testifies to the uniformity of different spectra and the autonomy of each of them. Structurally, the total complexity spectra correlate with the degree of disorder (imperfection) of the crystal and are related to the peculiarities of a defective performance such as a one-dimensional disorder. Three different types of spectra have three different principles of construction and behavior.

In the present work, we study the influence of adsorbed impurities, namely potassium atoms, on the energy spectrum of electrons in graphene. The electron states of the system are described in the frame of the self-consistent multiband strong-coupling model. It is shown that, at the ordered arrangement of potassium atoms corresponding to a minimum of the free energy, the gap arises in the energy spectrum of graphene. It is established that, at the potassium concentration such that the unit cell includes two carbon atoms and one potassium atom, the latter being placed on the graphene surface above a carbon atom at a distance of 0.286 nm, the energy gap is equal to [Formula: see text]0.25 eV. Such situation is realized if graphene is placed on a potassium support.

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