Shabatina T. I.
Reactions in Mesogenic Cyanphenyls at Low Temperatures and Cryoformation
of Metal-Mesogenic Nanosystems
Abstract
The results are presented for comprehensive experimental study (by IR,
UV- and ESR-spectroscopy) of specific interactions and reactions in molecular
and atomic-molecular systems of mesogenic cyanophenyls and their co-condensates
with metals at low temperatures. The quantitative parameters of mesogenic
cyanophenyls molecular association process in argon (4-10 K) and hydrocarbon
(77-100 K) matrices, solutions in nonpolar solvents and molecular condensate
films (80-350 K) are determined. The effect of
sample’s formation procedure and their thermal prehistory on molecular
organisation and kinetics of the model reaction of photoinduced nitroxides
formation is shown. Thermal evolution is considered for atomic-molecular
systems formed by low temperature co-condensation of some cyanophenyls with metal
(silver, copper) vapors on the cooled surfaces. The formation of metastable
complexes included in dimeric cyanobiphenyl structures are shown by IR, UV- and
ESR-spectroscopy in combination with
the results of quantum chemistry
modeling. It is established that thermal degradation of the complexes leads to nanosize metal
clusters formation and their further aggregation in anisotropic matrix. The
kinetic consideration of the processes
took place is proposed.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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