The structures of ethylene glycol, aminoethanol, ethylenediamine, and their dimers with the for mation of hydrogen bonds of different types are optimized by density functional theory (DFT) using hybrid functional B3LYP in the basis of 6 31++G(d,p), 6 311++G(2d,2p) and aug CC pVTZ. Energies of interac tions, hydrogen bond parameters, and oscillation frequency are calculated, and NBO analysis is performed. The types of hydrogen bonds formed in dimers of 1,2 disubstituted ethanes X-CH 2 -CH 2 -Y (X, Y = OH, NH 2 ) are established. Keywords: ethylene glycol, aminoethanol, ethylenediamine, intro and intermolecular hydrogen bonds, quan tum chemical methods of calculation.

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Dislocations in Magnetic Garnet Crystals1. Dislocations in magnetic flux-grown garnet crystals (Y3Fe,012 and others) have been observed. As a rule, { llO} growth pyramids have more defects than { 211 } ones.2. The highest content of defects (dislocation density 10,-lo4 cm-z) is observed in Y,Fe,O,, that grows on crucible walls adjacent to the free surface of the solution where the flow of heat is not uniform to the greatest degree. Bottom grown crystals usually have less dislocations. Far fewer dislocations are in wall grown crystals, least of all dislocations are contained in crystals that grow inside the solution. The solution pouring off at the end of the crystallization period increases dislocation density by some dozens.3. Heat treatment decreases dislocation density. The less dislocation content and the lower ordering are in the initial crystal, the higher heat treatment effectiveness.

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