Red oxygen crystals

[Martin]

normally one thinks of oxygen as a gas, that can be condensed to form a liquid

 

but at very high pressure molecular oxygen will crystalize to form a solid

 

the crystals of oxygen can have COLOR

in the range roughly 10-90 Gigapascal the crystal phase is called "epsilon" and it is RED color

http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf'>http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf

and a young Russian guy at Zurich ETH has succeeded in constructing a model that predicts crystal structures at various different levels of pressure

 

here is his webpage

http://olivine.ethz.ch/~artem/

 

the AIP Physics News Update picked up on this

http://www.aip.org/pnu/2006/split/784-1.html?source=rsspnu

 

The Journal of Chemical Physics published it June 2006 and

here is the technical abstract:

http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JCPSA6000124000024244704000001&idtype=cvips&gifs=yes

 

the published paper available PDF at his webside has a lot of pictures of crystal structures, and extra information. lots of different materials, not just oxygen. some stuff seems relevant to understanding how material deep in the earth acts

BTW he is very definite that the oxygen crystal is of MOLECULAR oxygen----this has been confirmed both experimentally and by his crystalization simulation program. It seemed interesting.

 

Here is the PDF

http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf'>http://olivine.ethz.ch/~artem/Publications/JChemPhys-USPEX-2006.pdf

[Locrian]

An impressive bit of modeling, to be sure. I remember reading in a paper once that below a certain size, gold molecules turn purple. I guess it's as they say: "The rules change in the reaches."

 

I'm somewhat interested in the expeirmental verifications - they used diamond anvil cells I presume? I don't see any information in those links and am too lazy to look on a sunday evening. If you run into anything would you make a quick post of it?