학술논문

Low-Temperature Magnetism of Gold Nano Particles Contained in Electrochemical Sugar Recognition System
Document Type
Periodical
Source
IEEE Transactions on Magnetics IEEE Trans. Magn. Magnetics, IEEE Transactions on. 55(2):1-4 Feb, 2019
Subject
Fields, Waves and Electromagnetics
Economic indicators
Temperature measurement
Temperature dependence
Gold
Magnetic susceptibility
Nuclear magnetic resonance
Gold nano particles (GNPs)
nuclear magnetic resonance (NMR)
paramagnetism
Language
ISSN
0018-9464
1941-0069
Abstract
Low-temperature magnetic properties were investigated on the gold nano particles (GNPs) with an average size of 11.5 nm, assembled with molecules of ruthenium complex (Ru0), and phenylboronic acid (B0) by the proton nuclear magnetic resonance ( 1 H-NMR) and susceptibility measurements. The temperature dependence of the NMR shift and the uniform susceptibility was described as the sum of the Curie–Weiss term and a positive constant term. From the former, the average number of Ru0 on each GNP was estimated to be 118, which is 23% of the calculation. The finite positive constant term shows a clear contrast with the well-known fact that the bulk gold is diamagnetic. Finally, a disappearance of the motional narrowing effect in the proton NMR spectra below 60 K indicates that the wavering motion of Ru0 complexes on GNP at room temperature is frozen at low temperatures.