Noble metals are metals that are resistant to oxidation, but the
definition is not exact. In the strictest sense, the definition of a
noble metal requires that the d-bands of the electronic structure are
filled, so they cannot accept covalent oxygen. Taking this into account,
only copper, silver and gold are noble metals, as all d-like band are
filled and don't cross the Fermi level, but we all know that copper is
rather reactive.
For platinum there are actually two d-bands which cross the Fermi level,
changing its chemical behavior to slightly reactive -- yet it has
limited "permanent" reactivity; consequently it is used as a catalyst,
whereas gold cannot catalyze anything.
Here is the Fermi surface database:
http://www.phys.ufl.edu/fermisurface/
The false color scheme is actually helpful in visualizing reactivity and
matrix structures.
Of most interest to LENR are Noble metals which are proton conductors
but will not easily retain hydrogen. IOW hydrogen bonds are weak or
nonexistent. Pd and Pt especially have this feature and also have a most
complicated relationship with oxygen. Nickel is close but is more
reactive, especially with oxygen. These two noble metals, Pd and Pt seem
to "want" to dissolve and to quickly capture some small amount of oxygen
easily, yet without forming strong covalent bonding. This unusual
property (when it occurs with oxygen) is known as "physisorption."
Wiki has an entry:
http://en.wikipedia.org/wiki/Physisorption
It is a physical adsorption process in which the adsorbate (oxygen in
this case) adheres and dissolves into the surface layer (usually less
than a nanometer of thickness) and is held through Van der Waals forces,
or weak intermolecular interactions rather than stronger covalent bonding.
Surprisingly, I have not been able to find a very thorough treatment of
this variable in the prior LENR literature. A google search for
[physisorption LENR] turns up two hits and they are only months old from
the recent 2007 APS March Meeting.
This may not be surprising actually, as my approach is rather unusual in
that it is coming from the POV of an investigator looking for (or else
trying to invent a rationale) how a hydrino catalyst (O++) which should
not be there, could in fact be there but have been overlooked -- and few
experimenters in CF give the Mills' hydrino much credence. And
correspondingly Mills pretends that he couldn't care less about CF. Too bad.
Here is the most ironic factoid -- almost everyone in CF admits to the
curious fact that active region on electrode surfaces is within the one
nanometer range of thickness - but heretofore never made the connection
with the presence of oxygen being important. It may or may not be
important - but the point is that it has inexplicably been overlooked
previously, AFAIK.
IOW the range in which oxygen physisorption is known to occur is the
very same so-called nuclear active environment (NAE) or nuclear active
spot (NAS) where fusion occurs, yet that "connection" up til now seems
to have been either neglected, or else assumed to be only coincidental.
More later, but let me say that even when adsorbed, oxygen is certainly
not ionic -- yet ... since the valency is rather unique with this atom,
the forthcoming argument that a "virtual O++ ion" is always available
when oxygen is adsorbed into Palladium, will be have to wait.
Jones
