Energy level diagrams Grotrian

The Grotrian diagram in Figure 7.9 gives the energy levels for all the terms arising from the promotion of one electron in helium to an excited orbital. 

S. Bashkin and J.O. Stoner, Atomic Energy Levels and Grotrian Diagrams. North-Holland, Amsterdam, 1975. 

The characteristic energy-level structure of these configurations is that of singlets or triplets, in accordance with the value 0 or 1 taken by S2. This structure is exhibited in the Grotrian diagram of Ybll 4f n 4d6s( D), KJ given in fig. 1.8. 

Figure 2.5 Energy levels and observed transitions in K. This type of diagram is commonly referred to as a Grotrian diagram. All of these low-lying energy levels arise from electron configurations of the type (1s) (2s) (2p) (35) (3p) (n/) = ...

C. E. Moore, Atomic Energy Levels, Circular 467, National Bureau Of Standards, vol. 1 (1949) S. Bashkin and J. 0. Stoner,Jr.,Atomic Energy Levels and Grotrian Diagrams (North-Holland, Amsterdam, 1975). 

Figure 23.6 The Energy Levels of the Hydrogen Atom and the Allowed Transitions between Them. This type of diagram is known as a Grotrian diagram.

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