Metal, 3d transition

Behm J M and Morse M D 1994 Spectroscopy of]et-cooled AIMn and trends in the electronic structure of the 3d transition metal aluminides J. Chem. Rhys. 101 6500... 

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... 

Oelkrug D (1971) Absorption Spectra and Ligand Field Parameters of Tetragonal 3d-Transition Metal Fluorides. 9 1-26... 

Investigations of the interaction between 3d transition metals and octahedral halide or oxide metal clusters led to the preparation of a number of novel cluster compounds such as the series AxByNbgClig (A = Li, K, Rb, Cs B=Ti, V, Mn, Cu) [33], and TizNbgOu [34]. 

Jonas K (1990) New findings in the arene chemistry of the 3d transition metals. Pure Appl Chem 62 1169-1174... 

Except for the elements at the ends of the rows, each transition metal can exist in several different oxidation states. The oxidation states displayed by the 3d transition metals are shown in Table 20-1. The most important oxidation states are highlighted in the table. The most common oxidation state for the 3d transition metals is +2, known for all the elements except Sc. Chromium, iron, and cobalt are also stable in the +3 oxidation state, and for vanadium and manganese the -H4 oxidation state is stable. Elements from scandium to manganese have a particularly stable oxidation state corresponding to the loss of ah the valence electrons configuration). 

Table 20-2 Representative Compounds of 3d Transition Metals in Their Commonly Occurring Oxidation States...

Figure 6.10. Schematic representation of the energy levels of a typical 3d transition metal. The extended s and p orbitals form the broad...

Late transition metal or 3d-transition metal irons, such as cobalt, nickel, and copper, are important for catalysis, magnetism, and optics. Reduction of 3d-transition metal ions to zero-valent metals is quite difficult because of their lower redox potentials than those of noble metal ions. A production of bimetallic nanoparticles between 3d-transi-tion metal and noble metal, however, is not so difficult. In 1993, we successfully established a new preparation method of PVP-protected CuPd bimetallic nanoparticles [71-73]. In this method, bimetallic hydroxide colloid forms in the first step by adjusting the pH value with a sodium hydroxide solution before the reduction process, which is designed to overcome the problems caused by the difference in redox potentials. Then, the bimetallic species... 

This alcohol reduction method is applied to the control of size and composition of not only the noble metal/noble metal [7] but the 3d-transition metal/noble metal nanoparticles [8] like magnetic FePt nanoparticles. 

First we consider the origin of band gaps and characters of the valence and conduction electron states in 3d transition-metal compounds [104]. Band structure calculations using effective one-particle potentials predict often either metallic behavior or gaps which are much too small. This is due to the fact that the electron-electron interactions are underestimated. In the Mott-Hubbard theory excited states which are essentially MMCT states are taken into account dfd -y The subscripts i and] label the transition-metal sites. These... 

Kitchin JR, Nprskov JK, Barteau MA, Chen JG. 2004. Modification of the surface electronic and chemical properties of Pt(lll) by subsurface 3d transition metals. J Chem Phys 120 10240-10246. 

Lee K, Savadogo O, Ishihara A, Mitsushima S, Kamiya N, Ota K-I. 2006. Methanol-tolerant oxygen reduction electrocatalysts based on Pd-3D transition metal alloys for direct methanol fuel cells. J Electrochem Soc 153 A20-A24. 

Table 9-8. Excitation Energies [eV] of 3d-Transition Metal Cations. ...

During the last years, more and more researchers have applied density functional theory to small transition-metal complexes and benchmarked the results against either high level wave function based methods or experimental data. A particular set of systems for which reasonably accurate benchmark data are available are the cationic M+-X complexes, where X is H, CH3 or CH2. Let us start our discussion with the cationic hydrides of the 3d transition-metals. 

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