Beyond Elements

[dkv]

HI ,

Kind of new to this forum.

We know Elements make the Compounds and in some cases we have strange structures which make Solids.

Can someone please explain to me the precise Structure in Metals?

How can an electron have freedom(delocalized) and yet hold on to the mettallic structure by behaving like a localized entity?

 

Thanks.

[RyanJ]

HI ' date='

Kind of new to this forum.

We know Elements make the Compounds and in some cases we have strange structures which make Solids.

Can someone please explain to me the precise Structure in Metals?

How can an electron have freedom(delocalized) and yet hold on to the mettallic structure by behaving like a localized entity?

 

Thanks.[/quote']

 

Well,the structure of a metalcan be said to be simmilar to that of a crystal, it has a regular lattice.

 

As far as I remember its because the d-orbital of the metal interferes with the s-orbital above it...

 

Cheers,

 

Ryan Jones

[woelen]

In metals, there is a so-called conduction band. Quantummechanically, inside an orbital, an electron can have a certain energy state. There are multiple orbitals in which electrons can be, but the energies associated with these are very distinct.

 

In a metal, multiple orbitals around different atoms combine to form a large number of very large orbitals, with energy levels very close to each other. So, in a piece of metal, there still are discrete energy levels, but there are many many energy levels, all inside a band between a lower and upper bound. So, it looks as if there is a continuum of energy levels. Because the energy levels are so very close to each other, electrons can easily move from one level to another level. Because the electrons in this way can move to another orbital very easily, it makes them mobile and hence a metal is a conductor.

 

The following link explains the semi-continuous behavior of metals (and semiconductors):

 

http://www.ece.utep.edu/courses/ee3329/ee3329/Studyguide/ToC/Fundamentals/Carriers/density.html

 

This is the entire site, which nicely explains more quantum mechanical concepts:

 

http://www.ece.utep.edu/courses/ee3329/ee3329/Studyguide/ToC/Fundamentals/index.html