budullewraagh - 11-6-2005 at 16:21
i was looking through a book on the elements today when i came across iridium. interestingly enough, it mentioned the Ir- oxidation state, as well as
the Ir+, which, apparently, are very rare. In addition, it mentioned a clathrate where iridium is at a neutral state.
Ir-1: [Ir(CO03(PPh3)]-
Ir(O): [Ir4(CO)12]
Ir+1: [Ir(CO)Cl(PPh3)2]
has anyone ever tried making any these? is anyone familiar with any of these?
the concept of reducing elemental iridium to an anion is most intriguing.
[Edited on 12-6-2005 by budullewraagh]
Pyridinium - 11-6-2005 at 18:01
That last one is called Vaska's Complex, I just looked it up in a book I have here. It has some very interesting properties.
The Ir-1 compound... wow, weird.
It looks like some of these are triphenylphosphine derivatives?
unionised - 12-6-2005 at 07:15
Negative oxidation states are not that unusual, Fe, Co, Ni and others do it. Almost all of these are complexes with CC, phosphines or (on a good day)
cyanide.
Borek - 12-6-2005 at 07:57
I wonder if you can really assign negative charge to the metal, or is it rather effect of calculation using standard oxidation numbers for all other
atoms in the particle.
neutrino - 12-6-2005 at 09:18
I'd bet that it actually is a negative charge. Considering the fact that anions of cesium have been made, Ir<sup>-</sup> doesn’t
seem so unlikely.
[Edited on 12-6-2005 by neutrino]