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. 

Figure 7.9 Grotrian diagram for helium. The scale is too small to show splittings due to spin-orbit coupling...

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

This has led to such cases in the history of chemistry that spectroscopic signals have been unidentified till newly discovered elements was found (e.g. rubidium, caesium, indium, helium, rhenium) or new species (highly ionized atoms, e.g. in northern lights [aura borealis], luminous phenomena in cosmic space and sun aura, such as nebulium , coronium , geocoronium , asterium , which was characterized at first to be new elements see Bowen [1927] Grotrian [1928] Rabinowitsch [1928]). 

Frank IE, Todeschini R (1994) The data analysis handbook. Elsevier, Amsterdam Grotrian W (1928) Uber den Ursprung der Nebellinien. Naturwiss 16 177... 

H. Gorke measured soln. between 2 and 60 per cent, cone., and between 0° and 100°. F. Kohlrausch and O. Grotrian give for the temp, coeff. of a 49 3 per cent, soln., a specific conductivity of K0(l +0 02350 +OOOOO1902), where K0 represents the specific conductivity at 0°. R. Dennhardt measured the relation between the viscosity and electrical conductivity. M. le Blanc found the decompositiou potential of a Y-soln., with platinum electrodes, at room temp., to be 2 08 volts, being thus about 0 08 volt less than the value for potassium and sodium nitrates. 

According to F. Kohlrausch and 0. Grotrian, the electrical conductivity of nitric acid increases as the cone, increases up to 30-33 per cent. HN03 and thereafter decreases. Measurements were also made by H. Crompton, E. Bouty,... 

E. Bouty found that nitrates dissolved in cone, nitric acid raise the conductivity in proportion to the amount dissolved. A. Klemenc and R. Scholler measured the conductivity of mixtures of nitrous and nitric acids, but obtained no definite evidence of the existence of H2N308. Observations on the temp, coeff. were made by P. Kohlrausch and O. Grotrian, C. Deguisne, and J. and G. E. Gibson. According to S. Arrhenius, the temp, coeff. between 18° and 52°, is ... 

CS2 (liq.). Data on the heat of vaporization were reported by Mathews,2 Mills,1 Wirtz,1 Winkelmann,2-3 Koref,1 Andrews,5 and Person.7 Vapor pressure data were reported by Battelli,1 Henning and Stock,1 Mund,1 Regnault,6-7 von Siemens,1 Rex,1 Stock and Seelig,1 Galitzine,1 Hannay,1 and Muller and Grotrian.1... 

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