Abstract
An attempt is undertaken to determine qualitatively, using the cryomatrix isolation method, the state of water cryocondensates in accordance with their cluster composition. To this end IR spectrometry is performed on thin cryovacuum condensate films formed from a mixture of water vapor and nitrogen in a combined condensation regime at substrate temperature T=16K. The water content in nitrogen in most experiments was 5%. The water partial pressure in the course of the experiments and the film thicknesses were determined in a way so that it would be possible to compare them with pure water films with the same reduced thickness grown at the same pressure and temperature. As a result of comparing our IR spectra with the data obtained by other authors it was concluded that water polyaggregates (H2O)n with different composition are formed in the process of combined condensation of water and nitrogen. In the concentration range studied, a large fraction of the polyaggregates consisted of dimers, and higher-order polyaggregates, right up to hexamers, were also present. In addition, the presence of a strong absorption band in the frequency range of librational vibrations is due to the presence of water microcrystallites in the nitrogen matrix. The presumed cyclical character of cluster formation made it possible to consider the clusters to be the nuclei of a crystalline phase. The short-range order parameters in the polyaggregates and microcrystallites formed can largely determine the character of the thermally stimulated polyamorphic and polymorphic transformations in amorphous solid water.