Pekka Pyykkö
Finnish professor of Chemistry at the University of Helsinki
Veli Pekka Pyykkö (born 12 October 1941) is a Finnish academic. He was professor of Chemistry at the University of Helsinki. From 2009–2012, he was the chairman of the International Academy of Quantum Molecular Science. He is known for his extension to the periodic table of elements, known as the Pyykkö model.
Pyykkö has also studied the relativistic effects present in heavy atoms and their effects in NMR.
Pyykkö model
After the 118 elements now known, Pekka Pyykkö predicts that the orbital shells will fill up in this order:
8s,
5g,
the first two spaces of 8p,
6f,
7d,
9s,
the first two spaces of 9p,
the rest of 8p.
He also suggests that period 8 be split into three parts:
8a, containing 8s,
8b, containing the first two elements of 8p,
8c, containing 7d and the rest of 8p.
The compact version:
Pekka Pyykkö correctly predicted the existence of chemical bonds between gold and the noble gas xenon, which is usually inert; this bond is known to occur in the cationic complex tetraxenonogold(II) (AuXe2+4). He also correctly predicted the existence of gold–carbon triple bonds.
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Biographical claims are most persuasive when dates, appointments and relationships can be traced to records created close to the events described. The source revision retrieved here is dated Jun 24, 2025. The linked authority identifier is Q7161093. VIAF identifies the subject as 49952184. The Library of Congress control number is n82233436. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1941, 2009 and 2012.
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This entry incorporates text from “Pekka Pyykkö” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.