Structural, electronic and magnetic properties of Ag_nFe clusters (n⩽ 15): local magnetic moment interacting with delocalized electrons

Abstract

The size-dependent electronic, structural and magnetic properties of AgnFe (n ⩽ 15) clusters have been investigated by using the density functional theory (DFT) within the generalized gradient approximation. The starting structures were generated from empirical genetic algorithm simulations. The most stable structures were then selected from a number of structural isomers based on the results of the further DFT calculations. The atom prefers to stay at the centre of the clusters. The 2D to 3D transition occurs at n = 6. The magnetic properties and the geometric structures are strongly correlated. For , the total magnetic moment of the cluster is quenched. The reason is similar to the Kondo effect in bulk metal. Also, is considered to be very stable according to the 18-electron counting rule.

A Systematic Investigation on CrCun Clusters with n = 9–16: Noble Gas and Tunable Magnetic Property

“…The behavior of Cu valence electrons to a certain extent is conceptually similar to the Kondo effect in larger systems: quenching the magnetic impurity. However, unlike what has been previously observed for Ag 10 Fe clusters the zero magnetic moment of CrCu 12 is attributed to the formation of an electronic shell closure rather than of a spin-compensating electron cloud …”

“…Studying single localized electronic states in size-selected clusters with a well-defined number of electrons thus becomes essential to understand the evolution of their alloy structure, stability, and magnetism. In this regard, gas-phased transition metal (TM) doped coinage metal clusters have been studied intensively by density functional theory (DFT) calculations − and experiments; the stability of TM doped gold and silver clusters (Au n TM + and Ag n TM + with TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were found strongly element- and size-dependent using photofragmentation technique; , large magnetic moments were identified for Au 6 – clusters doped with Ti, V, and Cr using photoelectron spectroscopy; a size-dependent transition from a local moment to a mixed valence regime was observed in singly chromium doped gold clusters by X-ray magnetic dichroism spectroscopy; and strong sp-d interaction was probed in photoelectron studies of cobalt doped silver anions …”

A Systematic Search for Structures, Stabilities, Electronic and Magnetic Properties of Silicon Doped Silver Clusters: Comparison with Pure Silver Clusters

“…The results exhibit that the doping clusters are more stable than the corresponding pure silver clusters. In light of the previous work [29], the doped iron atom prefers to stay at the center of the Ag n Fe (n ≤ 15) clusters. Moreover, numerous theoretical studies were carried out on various aspects of geometrical, electronic, and magnetic properties of doped silver clusters, such as Ag n Ni m , Ag n Au m , Ag n Pd m , and Ag n Y clusters [30 -33].…”

“…The isomers that correspond to high coordination numbers of Si-Ag bonds are found to be more stable. The doped silicon atom prefers to occupy the surface site of the Ag n Si clusters, which is different from the fact of iron doped silver clusters [29].…”

Theoretical Study of the Electronic Properties of Nickel Clusters

“…In this research, I established the calculations on the principles of spin-polarized density-functional theory (DFT) [12,13]. In terms of exchange and correlation functional, the Generalized Gradient Approximation (GGA) functional was applied according to the suggestions of Perdew, Burke and Ernzerhof (PBE) [14].…”