Res. Chem. Intermed.
, Vol. 29, No. 1, pp. 63– 70 (2003)
Also available online - www.vsppub.com
A dispersive model of radical accumulation in irradiated
, JUSTYNA STALUSZKA
, INGRID KOHL
and ERWIN MAYER
Institute of Applied Radiation Chemistry, Technical University of Lodz, Wroblewskiego 15,
93-590 Lodz, Poland
Institut für Allgemeine, Anorganische und Theoretische Chemie, Universität Innsbruck,
A-6020 Innsbruck, Austria
Received 13 May 2002; accepted 24 September 2002
Abstract—A dispersivemodel of radical accumulation in irradiated solids is discussed by the example
of hexagonal ice (Ih) and cubic ice (Ic) obtained by annealing of hyperquenched glassy water at 160 K.
The model assumes that radical production upon ° -irradiation is accompanied by their second-order
decay, which proceeds according to dispersive kinetics with the time-dependent speci c reaction rate
, where B
constant and ® is the dispersion parameter equal to 0.40 for both the
hexagonal and cubic ices. The radicals, OH in Ih, and OH plus HO
in Ic are produced at the same
rate upon ° -irradiation. The observed enhancement of radical accumulation in ice Ic in comparison
with Ih is due to the marked decrease of radical recombination in ice Ic. This is rationalized by the
hindrance of radical transport in the lattice of ice Ic containing substantial amounts of Bjerrum-type
: Irradiated solids; hexagonal ice; cubic ice; hyperquenched glassy water; radicals.
In recent years we have extensively studied radicals produced by
metastable forms of solidi ed water [1 –6]. Our primary objectives were (i) to use
hyperquenched glassy water (HGW) as a model of liquid water for examination
of radiation damage to dissolved biomolecules and (ii) to use vapor-deposited
amorphous solid water (ASW) and cubic ice (Ic) as laboratory models of water ices
Deceased 5 September 2001.
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