Ab initio calculations for studying electronic band structure of ideal and defective Cd 1 -x Mn x Se (0.01 ≤ х ≤ 0.07) semimagnetic semiconductors have been performed. It has been defined that with an increase in concentration of Mn in Cd 1 -x Mn x Se compound, there is a decrease in the band gap. Based on the results obtained we can conclude that ferromagnetic phase is more stable than antiferromagnetic one. It has been found that defects such as vacancy, interstitial atom, and Frenkel pair lead to an increase in the band gap, change in the total energy, and formation of local levels in the band gap.

This work is devoted to theoretical investigations of Cd1-xMnxS semimagnetic semiconductors (SMSC). The purpose of this work was to calculate the electronic band structure of ideal and defective Cd1- xMnxS SMSC in both antiferromagnetic (AFM) and ferromagnetic (FM) phases. Ab initio, calculations are performed in the Atomistix Toolkit (ATK) program within the Density Functional Theory (DFT) and Local Spin Density Approximation (LSDA) on Double Zeta Double Polarized (DZDP) basis. We have used Hubbard U potential UMn = 3.59 eV for 3d states for Mn atoms. Supercells of 8 and 64 atoms were constructed. After the construction of Cd1-xMnxS (x = 6.25 %; 25 %) supercells and atom relaxation and optimization of the crystal structure were carried out. Electronic band structure and density of states were calculated, the total energy has been defined in antiferromagnetic (AFM) and ferromagnetic (FM) phases. Our calculations show that the band gap increases with the increase in Mn ion concentration. It has been established that Cd or S vacancy in the crystal structure leads to the change of band gap, Fermi level shifts towards the valence or conduction band.

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Primary stage of influence of the external physical factor are some conformative transformations of fibers-receptors which start the intensifying cascade of biochemical reactions. Thus energy of external influence can be on usages of less response of a cage. After an initial stage of absorption of the electromagnetic radiation, one of mechanisms of realisation of action of electromagnetic radiation of a microwave range on live organisms considers updating freely radicalthe reactions proceeding in cages and fabrics under the influence of electromagnetic energy. Problem of studying of influence of nonionising electromagnetic radiation is revealing and an effect explanation at level of the whole organism, at level of the central nervous system. Researches of influence of electromagnetic radiations on biosystems are spent basically in 2 frequency ranges: ultralow electromagnetic frequencies (1-20Hz) and ultrahigh electromagnetic frequencies (0.3GHz-300GHz). The greatest potential danger to biological objects radiations with frequencies which possessing getting action, influence both an organism as a whole, and on its touch and effectorive systems represent, fabrics and various reseptorive structures. In vivo and in vitro experiments with an irradiation were spent on the snakes containing in standartive conditions. Snakes (Vipera lebetina obtusa) were subdivided on two groups, each of 5 snakes. The skilled group of snakes was exposed to an irradiation in a current of 4 minutes. The skilled group of snakes was exposed to an irradiation. Radiation source was the UHF generator. Frequency of radiation has been chosen on the maximum factor of absorption of poison. The irradiation of animals was spent in the special chamber and depending on the purpose of experiments for realisation of modes high (U-14000B) and low (U-7000B) intensity of an irradiation target capacities of a radiator -P -70Bt were applied. In a day, 2, 3, 4 and 5 days after an irradiation of snakes we took venom, dried up poison in cups Petri placed in eksikator over steams of chloride calcium. After venom drying defined fiber total on method Bpedf • pda. Simultaneously definition of toxicity of venom was spent on white three-monthly rats. It is necessary to notice, that at an irradiation of snakes electromagnetic radiation of low intensity did not mark change of quantity of the general fiber in poison of snakes. Toxicity of venom also was not exposed to changes. At high intensity of radiation insignificant fluctuations in the maintenance of the general fiber and toxicity of venom of snakes were observed.