A New Kind of Chemistry

pq writes "Reasearchers at VCU, Pennsylvania State have created "superatoms" of aluminium and iodine that behave like the alkaline earth metals. From the article: "Our production of such a species is a stirring development that may lead to new compounds with a completely new class of chemistry and applications". Another article on Biomedcentral"

Comments

Re:Ugh... Get your facts

[AlgaeEater]

Corrosion. def: a state of deterioration in metals caused by oxidation or chemical action.

Corrosion tends to be used for a continual process of deterioration whereas the oxidation coating formed on aluminium is very stable and prevents any further corrosion. A similar thing happens with the carbon lattice in diamond; it is a hydrogen coating rather than oxygen though.

AE

Re:Ugh... Get your facts

[myukew]

corrosion is an ongoing process as long as the environment doesn't change, like with iron and water.

aluminium gets this ultra thin oxide layer and doesn't react any further.
so they're right

Re:Chemical Bonding?

[Dachannien]

Well, there are some non-first-year concepts at work here. From looking at the Science* article (14 Jan 2005 issue, p 231-235), I gather that the aluminum atoms form a small "jellium" cluster. Within a cluster of this type, the electrical potential is relatively uniform, but there are boundary effects at the edge of the cluster.

In the Al13 cluster, the inner electrons are kept in normal ground states, and combined with the atoms' protons, form a net positive charge. The outer (valence) electrons react to this charge by falling into energy states dependent upon the whole Al13 molecule, not the individual atoms. In fact, the molecule's energy states can resemble those of other atoms, and can behave in the same ways that those other atoms do. Al13, for example, resembles a halogen, and so it binds to varying numbers of iodine atoms covalently.

Now, I'm not actually a chemist (I was brought up in electrical engineering and computer science), so my reading of the details might be wrong, but I think that's how it works.

(* You'll either need a Science subscription, or you'll need to access from the domain of an institution that has a site subscription. The vast majority of US universities do.)

Re:The stories seem to contradict each other

[Lars T.]

The sentence from the Times Dispatch is refering to the Al13 cluster, the Scientist talks about the Al14 cluster.