(
)
V.F. Plyusnin et al.rChemical Physics Letters 325 2000 153–162
161
bands with similar maximum at 645 and 600 nm,
Acknowledgements
v
respectively. The absorbing center of the DTP radi-
cal consists of the S–P–S group which also has a
long-wave absorption band with a maximum at 616
The financial support of the Russian Foundation
Ž
for Basic Research Grants No. 99-03-33308 and
nm. The quantum-chemical calculations show that
.
99-03-32272 , Russian Federal Scientific Program
v
the unpaired electron of the dtc radical is on the
Ž
.
‘Integration’ Grant No. 274 and Zamaraev Charita-
ble Scientific Foundation is gratefully acknowledged.
The authors also express gratitude to Prof. S.F.
Vasilevsky for a kind giving of a samples of nitroxyl
radicals.
s)-orbital and the absorption band belongs to the
electron transition s s) 27 . The composition
w
x
identity and closeness of the spectra allow us to
v
v
assume that XAN and DTP are also the s-radicals.
Calculations using the HyperChem5 program in the
framework of AMI and PM3 methods and multicon-
figuration interaction confirm the occurrence of tran-
sitions in the radicals of this type centered in the red
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