Huber's empire in Martinsried had a cabinet with ~500 compounds, many
of them synthesized by himself (occasionally blowing up a lab in the
process...) that in fact contained thorium, hafnium, etc. compounds.
Radioactive compounds were kept in a little lead box. I am not aware
of any successful derivatization with the heavy atoms you mention, but
it certainly wasn't for lack of trying... Some of us went through
hundreds of trials to get phases. That was in the early to mid 90's. I
just checked my own dissertation and found that I had indeed used
dysprosium and hafnium. Since these were not successful I should
probably write them up and publish in the Journal of Failed
Crystallization Experiments. Cheers - MM
--------------------------------------------------------------------------------
Mischa Machius, PhD
Associate Professor
Department of Biochemistry
UT Southwestern Medical Center at Dallas
5323 Harry Hines Blvd.; ND10.214A
Dallas, TX 75390-8816; U.S.A.
Tel: +1 214 645 6381
Fax: +1 214 645 6353
On Apr 1, 2009, at 9:21 AM, Thomas Womack wrote:
A perusal of the PDB reveals that the game of Periodic Table bingo
still
has eleven rounds to run:
scandium, titanium, germanium, zirconium, niobium, neodymium,
dysprosium, thulium, hafnium, bismuth and thorium remain absent from
PDB
entries.
OK, many of these are elements that would rather be refractory
oxides or
jet-engine components than hexammines, and niobium chloride clusters
don't seem to be as water-stable as Ta6Br14, but why have neodymium,
dysprosium and thulium so consistently been left out there in the cold
rather than admitted to the warmish embrace of carboxyl groups? There
must somewhere be a protein with a site that cries out for
ThCl2(2+), an
unexpectedly water-stable cation.
Tom
