Sciencemadness Discussion Board

Why is osmium tetroxide volatile?

Scalebar - 4-3-2017 at 08:59

I work with electron microscopes and work with this stuff every week. I'm used to the double gloves, the face shields, the fume extraction and all the other things that stop it from killing me but there's one thing about I just don't understand and that makes it even worse to handle.

What business does a soluble 254 Da metal containing molecule have in evaporating from solution? I mean looking at it on paper, it just doesn't seem like that should be possible yet the inside of the secondary container gets stained with the stuff after a few days in the fridge and the fume hood ceiling is distinctly grey.

Is there an explanation? ( one that I could understand )

DraconicAcid - 4-3-2017 at 09:58

It's tetrahedral and non-polar, just like tin tetrachloride, which is also volatile.

unionised - 4-3-2017 at 10:25

Ditto tetramethyl lead.

clearly_not_atara - 4-3-2017 at 13:14

TiCl4, CrO2Cl2, VOCl3, VO(NO3)3, Cu(NO3)2, WF6, etc are examples of the phenomenon where metals in their highest oxidation state can prefer to form molecules rather than ionic crystals