Dimension-Dependent Magnetic Behavior of Manganese-Cysteine Inorganic Complex Nanoparticles

Abstract

A cysteine-based complex of Mn 2+ led to the formation of nanoparticles in aqueous medium under ambient conditions. The formation and evolution of the nanoparticles in the medium were followed by ultraviolet-visible light (UV−vis) spectroscopy, circular dichroism, and electron spin resonance spectroscopy that also revealed a first-order process. The magnetic properties of the nanoparticles isolated as solid powders exhibited strong crystallite and particle size dependence. At low crystallite size, as well as particle size, the complex nanoparticles showed superparamagnetic behavior similar to other magnetic inorganic nanoparticles. The magnetic nanoparticles were found to undergo a superparamagnetic to ferromagnetic transition, and then to paramagnetic transition with a gradual increase in either their crystallite size or particle size. The discovery of dimension-dependent magnetic property of inorganic complex nanoparticles may usher in a superior option for tuning the magnetic behavior of nanocrystals, depending on the component ligands and metal ions.

Influence of dimensionality on optical properties of doped assembly of gold nanoclusters

“…It may be noted here that interaction between Mn 2+ ions in Mn 2+ –cysteine complex nanoparticles has been reported to result in size-dependent magnetic properties, including the emergence of super-paramagnetism in smaller particles. 53,54…”

Moiré Superlattices of Zn2+ Mediated 2D Assembly of Mn2+-Cysteine Complex Nanoparticles Alter Electron Spin Transitions in the X-band

“…The uniform-sized (<4 nm) Mn-Cys inorganic complex nanoparticles were prepared as dispersion after completion of a minimum of 24 h reaction followed by centrifugation of the large particles. [37] The dispersion containing poorly crystalline Mn-Cys nanoparticles were subjected to assemble by complexation reaction with Zn 2+ ions. The reaction was allowed to continue for at least 24 h, till the mixture turned opaque in this course of time.…”