Primary study on solvent effect of COCA4 by laser photolysis

LOW ENERGY ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS

Primary study on solvent effect of COCA4 by laser photolysis

CHENG Kemei，

YAO Side，

YUAN Lihua

Nuclear Science and Techniques

Vol.18, No.5

pp.272-275

Published in print 20 Oct 2007

DOI：10.1016/S1001-8042(07)60060-8

CLC：O644.18,O644.22,O621.1,O625.42

39100

Reaction of p-tert-oxocalix[4]arene in acetonitrile (CH₃CN) by 308nm laser pulses was investigated to understand its mechanism as polymer stabilizer. Four main absorption bands were observed at 300nm, 400nm, 460nm and 540nm. The 300nm absorption was assigned to the absorption of phenoxy radical, and the 460nm and 540nm were triple state absorption. It was concluded that the relative stable phenoxy radical mediate was formed through intramolecular energy transition of carbonyl triplet after laser excitation in CH₃CN. The formation mechanism of phenoxyl radical was quite different from that in cyclohexane (C₆H₁₂), which was cooperation of two-photon process and one-photon process.

p-tert-oxocalix[4]areneLaser photolysisTriple stateAcetonitrile

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