An extended periodic table with 54 predicted elements has been mapped out by Pekka Pyykkö, University of Helsinki, Finland.
He has used a highly accurate computational model to predict electronic structures and therefore the periodic table positions of elements up to proton number 172 – far beyond the limit of elements that scientists can currently synthesise.

The extra 54 super heavy elements predicted may exist under extreme conditions with very short lifetimes owing to radioactive decay, but have not yet been synthesised and Pyykkö does not expect this to happen anytime soon.

Although the experimental results may never appear, the basic physics of the problem are sound according to Pyykkö.

• A suggested periodic table up to Z 172, based on Dirac–Fock calculations on atoms and ions
  Pekka Pyykkö,
  Phys. Chem. Chem. Phys. 2010
  DOI: 10.1039/c0cp01575j