A glowing report on phosphorus
Phosphorus in a cage could adopt the benzvalene structure
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Making stable compounds containing only
phosphorus but with more than four atoms has been possible only on the computer
screen until now, Helmut Schwarz and his colleagues at The Technical University of Berlin decided that it was about time there was something approaching a 'buckyball', or even a sulphur ring, for phosphorus chemists and set about aiming towards that goal.
So far, they have detected minute amounts of a molecule containing six phosphorus atoms, which is a tenth the number of atoms as there in buckminsterfullerene, but better than the previously available four-phosphorus species.
The team has generated the P6 molecule only in the vanishing environment of a mass spectrometer by fragmenting a precursor molecule a tricyclic polyphosphane - an organo-P6 compound containing two pentamethylcyclopentadienyl groups. The immediate thought for the shape of the molecule is that it would be a tiny hexagon - not dissimilar to the familiar benzene ring. However, Schwarz and his colleagues know only too well that phosphorus compounds tend to form cages and are betting on a cage-like structure.
The likelihood of this species having an exotic and extensive chemistry of its own is small though, the researchers believe. They suspect it will exist only fleetingly before rearranging to a more stable form... But, they are working on creating more complex structures with more phosphorus atoms with the assistance of computer models to help them design suitable precursors. Maybe one day we'll all be talking about the all-phosphorus soccer ball just as we did with the all-carbon buckyball.
Angewandte Chemie English Edition, 1999, 38(23), 3513.
