IR-active vibrational modes of CdTe, CdSe, and CdTe/CdSe colloidal quantum dot ensemblesстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 19 июля 2013 г.
Аннотация:The frequencies of the vibrational modes of CdTe and CdSe quantum dots and
CdTe/CdSe core/shell nanoparticles prepared by the colloidal chemistry method are determined
using IR transmission and IR reflection spectroscopy. The experimental IR transmission
spectrum of CdTe and CdSe nanocrystals exhibits a broad minimum located between the
frequencies of the transverse (TO) and longitudinal (LO) optical phonons of bulk CdTe and
CdSe crystals. The frequencies of the modes for ensembles of CdTe and CdSe quantum dots
are considerably shifted toward lower frequencies as compared to those calculated for single
quantum dots. This is explained by the dipole-dipole interaction between quantum dots. The
frequencies of modes for the structures with core/shell nanoparticles differ little from the
calculated frequencies. This suggests a weakening of the interaction in these structures due to
the enhancement of dielectric screening.