Re: Hard metals

"Jorg Schuhmacher" <[EMAIL PROTECTED]> wrote:

> I am looking for information (a review) on hardmetals in particular tungsten
> carbide, tungsten nitride, Tantalum nitride, adressing the electronic
> structure and bonds in these materials. Is the concept of  oxidation numbers
> useful in describing them?

I do not have a reference a hand, but I remember x-ray absorption 
near-edge spectra of thse materials that show how the electronic 
structure mainly behaves like a rigid band. The nitride has one more 
electron per formula unit, filling up the d-bands around the 
fermi-level, that kind of trends.

-- 
Pieter.Kuiper @ msi.vxu.se           http://www.masda.vxu.se/~pku/