Transition-metal clusters magnetic properties

One of tire interesting aspects of transition-metal clusters is tlieir novel magnetic properties [91, 92, 93 and 94l]. ... 

Pastor G M, Dorantes-Davila J and Bennemann K H 1989 Size and structural dependence of the magnetic properties of small 3d-transition metal clusters Phys. Rev. B 40 7642... 

Size and Structural Dependence of the Magnetic Properties of 3d Transition Metal Clusters. 

The accurate quantum mechanical first-principles description of all interactions within a transition-metal cluster represented as a collection of electrons and atomic nuclei is a prerequisite for understanding and predicting such properties. The standard semi-classical theory of the quantum mechanics of electrons and atomic nuclei interacting via electromagnetic waves, i.e., described by Maxwell electrodynamics, turns out to be the theory sufficient to describe all such interactions (21). In semi-classical theory, the motion of the elementary particles of chemistry, i.e., of electrons and nuclei, is described quantum mechanically, while their electromagnetic interactions are described by classical electric and magnetic fields, E and B, often represented in terms of the non-redundant four components of the 4-potential, namely the scalar potential and the vector potential A. 

Several recent studies have been devoted to understanding and predicting the magnetic and spectroscopic properties of oligonuclear transition metal clusters, concentrating particularly on... 

The University of Montreal showed much foresight with the appointment of Dennis Salahub in 1976. In the next two decades he made several key contributions to the development and applications of density functional (DF) methodology. His early work with the Xa method22 helped to explain diverse complex phenomena in the area of transition metal clusters, their electronic and magnetic properties, and their use as models for chemisorption and catalysis. Explanations emanating from calculations on the reduction of surface mag-... 

The electronic state calculations of transition metal clusters have been carried out to study the basic electronic properties of these elements by the use of DV-Xa molecular orbital method. It is found that the covalent bonding between neighboring atoms, namely the short range chemical interaction is very important to determine the valence band structure of transition element. The spin polarization in the transition metal cluster has been investigated and the mechanism of the magnetic interaction between the atomic spins has been interpreted by means of the spin polarized molecular orbital description. For heavy elements like 5d transition metals, the relativistic effects are found to be very important even in the valence electronic state. 

Let us explain optical absorption spectra of cluster ions of transition metals containing Sd valence electrons. It is well-known that 3electron correlation and exhibit specific magnetic properties. In this section, we describe the magnetic properties of several transition metal-cluster ions derived from their optical absorption spectra and photoelectron spectra in combination with theoretical analyses. ... 

Electron spin resonance (ESR) has sometimes been used to characterize electronic and structural properties of transition-metal clusters embedded in frozen rare-gas matrices. Neglecting the spin-orbit coupling, the interaction between electrons and the nuclear magnetic moment of each atom in the cluster can be expressed by the simple Hamiltonian [116, 117] ... 

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