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Published on: October 9, 2012
Spectroscopic behavior of cationic metallophthalocyanines in the presence of anionic quantum dots
Mopelola Idowu1, Tebello Nyokong
1Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa.
Abstract:
The interactions and spectroscopic properties between cationic zinc phthalocyanine derivatives (peripherally and non-peripherally tetrasubstituted and peripherally octa substituted with 2-diethylmethylaminoethylsulfanyl (betaTZnPc, alphaTZnPc and betaOZnPc)) and CdTe core quantum dots (QDs) capped with mercaptopropionic acid or thioglycolic acid (represented as CdTe@MPA and CdTe@TGA, respectively) have been studied in methanol:water mixture. Strong coupling of MPcs was deduced from the interaction since the UV-vis spectroscopic studies of the ground state complex formed on mixing both components showed loss of the phthalocyanine monomeric band with the formation of a dimeric band (spectrum of aggregated species). The dimerization constants were of the order of 10(4)M(-1).
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