‎"LANDÉ, A.‎
‎Termstruktur und Zeemaneffekt der Multipletts.Braunschweig, - [FIRST APPEARANCE OF THE ""LANDÉ INTERVAL RULE""]‎

‎Berlin, Springer, 1923. 8vo. Bound in contemporary halfcloth. In ""Zeitschrift für Physik"", Bd. 15. Entire volume offered. A stamp on front free end paper and title page, light wear to extremities. Pp.189-205. [Entire volume: IV,420 pp].‎

Reference : 49491

‎First appearance of Lalandé important paper in which the ""Landé interval rule"" was introduced for the very first time.""Lalandé interval rule states that when the spin-orbit interaction is weak enough to be treated as a perturbation, an energy level having definite spin angular momentum and orbital angular momentum is split into levels of differing total angular momentum, so that the interval between successive levels is proportional to the larger of their total angular momentum values."" (Morris, (1992). Academic Press dictionary of science and technology. P. 1201).‎