Journal of Physical Studies 3(4), 437–450 (1999) DOI: https://doi.org/10.30970/jps.03.437 DISLOCATIONS IN MOLECULAR CRYSTALS

P. O. Kondratenko
Supreme Attestation Commission
34 Khreshchatyk Str., Kyiv, UA-01001, Ukraine

The review is dedicated to the specificity of generation and movement of dislocations observed in molecular crystals. It is marked that for these processes the presence of a considerable compensatory effect caused by the presence of a rotary degree of freedoms in molecules is characteristic. Together with minor forces of an intermolecular interaction it results in the fact that the motion of dislocations can be caused not only by stresses in a chip but and by thermoactivative processes. On the example of single crystals of anthracene the existence of several types of generation centers of dislocations in molecular crystals is detected. It is shown, that the movement of a dislocation on the value of the Burgers vector is described at room temperature as a diffusive motion of a sin–Gordon soliton and at the temperature close to that of sublimation or as a motion of a free sin–Gordon soliton. The excitation and radiation of molecules in the neighbourhood of dislocations is being surveyed. It is shown that such an excitation is localized on an axis of a dislocation as an unidimensional dislocation exciton.

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