Size‐Controlled <i>Ex‐nihilo</i> Ferromagnetism in Capped CdSe Quantum Dots

Abstract

Hysteresis loops in D = 1.8 nm CdSe-TOPO nanoparticles show ferromagnetism at 5 K and 300 K. Charge transfer from Cd to the Cd–O bond is shown by arrow in the Fourier transforms amplitudes of the EXAFS k2χ data at the Cd K-edge in the smaller 2.8 and 4.1 nm particles. This charge transfer produces holes in the Cd 4d band yielding ferromagnetism varying as 1/D with magnetic moment µ = 0.0075 µB per Cd surface atom.