Evidence for ligand-induced paramagnetism in CdSe quantum dots.
نویسندگان
چکیده
We report evidence that paramagnetism in CdSe QDs can be induced via manipulation of the surface chemistry. Using SQUID magnetometry and X-ray absorption spectroscopy, we demonstrate that the paramagnetic behavior of the CdSe QDs can be varied by changing the ligand end-group functionality of the passivating layer. Contrary to previous reports, no evidence for ferromagnetism was observed. The results suggest that the paramagnetism is induced via pi back-bonding between Cd 4d orbtials and ligands with empty pi* orbitals.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 131 20 شماره
صفحات -
تاریخ انتشار 2009