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ZnO Nanoparticle Size-dependent Excitation of Surface Raman Signal from Adsorbed Molecules: Observation of a Charge-Transfer Resonance

NCJ Number
Applied Physics Letter Volume: 91 Dated: 2007 Pages: 221106
Date Published
0 pages

This article reports on a project that found by observing the Raman intensity of several molecules (4-mercaptopyridine and 4-mercaptobenzoic acid) adsorbed on the surface of ZnO nanocrystals as a function of particle size in the range of 18–31nm diameter, a large increase in intensity near 28nm occurred. 


This is an indication of a size-dependent charge-transfer resonance. This effect is interpreted by the authors as due to formation of a charge-transfer complex between a surface-bound exciton and the adsorbed molecule. (publisher abstract modified)

Date Published: January 1, 2007