166
VLASOVA et al.
spin relaxation time) is much shorter than T1 (spin–
lattice relaxation time). This is typical of magnetically
diluted paramagnets [4]. The relaxation time for polyꢀ
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π
ꢀ
T
ꢀ
π
/2ꢀ π/2ꢀ
τ
ꢀ
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for T1 and
τ
ꢀ
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π
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20 ns,
τ
= 200 ns, and T = 1000 ns [7].
Thus, this study has revealed the possibility to use
acyl iodides as reagents in the photochemical
exchange of chlorine or bromine atoms for iodine in
haloarenes and for the photochemical preparation of
α
, ꢀdiiodopolyarylenes, polymers showing paramagꢀ
ω
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DOKLADY CHEMISTRY Vol. 438
Part 2
2011