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. Pyykkö model Pyykkö-displaced elements are in boldface 8 119Uue 120Ubn 121Ubu 122Ubb 123Ubt 124Ubq 125Ubp 126Ubh 127Ubs 128Ubo 129Ube 130Utn 131Utu 132Utb 133Utt 134Utq 135Utp 136Uth 137Uts 138Uto 141Uqu 142Uqb 143Uqt 144Uqq 145Uqp 146Uqh 147Uqs 148Uqo 149Uqe 150Upn 151Upu 152Upb 153Upt 154Upq 155Upp 156Uph 157Ups 158Upo 159Upe 160Uhn 161Uhu 162Uhb 163Uht 164Uhq 139Ute 140Uqn 169Uhe 170Usn 171Usu 172Usb 9 165Uhp 166Uhh 167Uhs 168Uho s-blockg-blockf-blockd-blockp-block 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) (). He also correctly predicted the existence of gold–carbon triple bonds.Scientific American June 2013, "Cracks in the Periodic Table". p. 72.
References