Magnetic valence

SPD singular point detection (method) (ZJ average magnetic valence... 

The second group comprises calculations of the band structures and related properties. This also includes the so-called magnetic valence model , which is a modification of the band approach. 

Here (i) is the number of 3d electrons in the Fe spin-up band, (ii) Z, is the chemical valence of atom i, (iii) Nip is the number of electrons in the unpolarized s-p conduction bands and (iv) (Zn,) is the average magnetic valence of the compounds, which for the pseudotemaries considered by Christides et al. (1991b) has the form... 

Fig. 13. Magnetic moment as a function of magnetic valence for Gd-Co and Gd-Co-B systems. After Due and Givord (1995b).

In absorption spectroscopy a beam of electromagnetic radiation passes through a sample. Much of the radiation is transmitted without a loss in intensity. At selected frequencies, however, the radiation s intensity is attenuated. This process of attenuation is called absorption. Two general requirements must be met if an analyte is to absorb electromagnetic radiation. The first requirement is that there must be a mechanism by which the radiation s electric field or magnetic field interacts with the analyte. For ultraviolet and visible radiation, this interaction involves the electronic energy of valence electrons. A chemical bond s vibrational energy is altered by the absorbance of infrared radiation. A more detailed treatment of this interaction, and its importance in deter-... 

Pure iron is a silvery white, relatively soft metal and is rarely used commercially. Typical properties are Hsted in Table 1. Electrolytic (99.9% pure) iron is used for magnetic cores (2) (see Magnetic materials, bulk). Native metallic iron is rarely found in nature because iron which commonly exhibits valences of +2 and +3 combines readily with oxygen and sulfur. Iron oxides are the most prevalent form of iron (see Iron compounds). Generally, these iron oxides (iron ores) are reduced to iron and melted in a blast furnace. The hot metal (pig iron) from the blast furnace is refined in steelmaking furnaces to make steel... 

Compound CAS Registry Number V anadium valence No. of d electrons Magnetic moment, J/T X 10-23" Color... 

In his valence bond theory (VB), L. Pauling extended the idea of electron-pair donation by considering the orbitals of the metal which would be needed to accommodate them, and the stereochemical consequences of their hybridization (1931-3). He was thereby able to account for much that was known in the 1930s about the stereochemistry and kinetic behaviour of complexes, and demonstrated the diagnostic value of measuring their magnetic properties. Unfortunately the theory offers no satisfactory explanation of spectroscopic properties and so was... 

The difference between the two extremes is essentially that, in the former, the Re retains its valence electrons in its d orbitals whereas in the latter it loses 6 of them to delocalized ligand orbitals. In either case paramagnetism is anticipated since rhenium has an odd number of valence electrons. The magnetic moment of 1.79 BM corresponding to 1 unpaired electron, and esr evidence showing that this electron is situated predominantly on the ligands, indicates that an intermediate oxidation state is involved... 

MAGNETIC DICHROISM IN VALENCE BAND X-RAY PHOTO EMISSION SPECTROSCOPY... 

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