Irving Williams series

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The Irving Williams series was named after the chemists Harry Munroe Napier Hetherington Irving (1905-1993) and Robert Joseph Paton Williams (1926-2015). In 1948, they published an article in the scientific journal Nature about research on trends in the stabilities of complexes of divalent ions of transition metals of the fourth period . When using different ligands , there was always an increase in stability from manganese through iron, cobalt and nickel to copper and then a decrease to zinc. This "stability trend series" was named after them as the Irving Williams series .

The series

Ba (II) <Sr (II) <Ca (II) <Mg (II) <Mn (II) <Fe (II) <Co (II) <Ni (II) <Cu (II)> Zn (II)

Explanation

i) If we consider a period , the shielding of the 3d orbitals decreases with increasing atomic number . The metal ion radius decreases, increasing the Lewis acid strength and thus strengthening the ML bond.

ii) We get additional stabilization from the ligand field stabilization energy and further electrons in the t2g band.

iii) Due to the Jahn-Teller distortion , Cu (II) experiences an astonishingly high level of stabilization.

literature

  • H. Irving, R. Williams. Nature, 162, 746 (1948)
  • RD Shannon, CTPrewitt, Acta Crystallogr., 1969, 925-946
  • Shannon RD, Acta Crystallogr., 1976, 751-767