Lars Vegard, atomic structure, and the periodic system

The Norwegian physicist and phys. chemist Lars Vegard (1880-1963) did significant work also on the borderline between chem. and physics, in particular as related to X-ray spectroscopy, crystallog., and solid state chem. In 1918, Vegard suggested configurations of all the elements and on this basis an explanation of the entire periodic system. In fact, his periodic system of that year is probably the first system of its kind, later to be improved by Niels Bohr, Edmund Stoner, and, finally, Wolfgang Pauli. This paper focuses on Vegard's early attempt, made in works between 1916 and 1920, to understand the structure of the chem. elements in terms of the electron configurations of atoms.