﻿Aspects of the JSfeon Spectrum. 213 



whereas there are many more lines in existence. These lines 

 can only be explained by the fact that when the spectrum is 

 obtained, large numbers of ionized atoms exist, and under 

 such circumstances our fundamental equations no longer 

 hold. 



The discussion of the properties of ionized atoms is very 

 complex, since the possible degrees and modes of ionization 

 are very numerous. The first case which comes under con- 

 sideration is the atom which has lost one electron, thus 

 leaving an excess of one positive charge. 



It is very probable that one of the outer electrons will be 

 removed, thus leaving seven electrons in the outer shell. 

 Now, it seems probable that the angular momentums of the 

 remaining electrons will suffer no change, the light pro- 

 duced during ionization being due solely to the change of 

 energy of the electron suffering removal. We are thus left 

 with seven electrons, each possessing the same angular 

 velocity. It is a matter of considerable difficulty to arrange 

 these electrons, and it is impossible to arrange them on a 

 spherical surface without the force acting on an electron 

 varying with the electron taken. We are therefore obliged 

 to separate them into different shells. 



Now, since the angular momentums of our seven outer 

 electrons are the same, it follows that, if they are not on the 

 the same spherical surface, then they must be in motion 

 relative to one another. Under such conditions the positions 

 of the electrons will vary with time. 



Owing to the complexity of such a case, it seems impossible 

 to treat the case mathematically without more experimental 

 evidence. There are further atoms present which have been 

 ionized to a greater extent, thus losing several electrons. 

 Similar difficulties are met with in the cases of atoms with 

 five or six electrons in the outer shell as in the case of seven 

 electrons. The cases in which four or six electrons have 

 been removed are, however, considerably simpler, since the 

 electrons may then be given positions on a spherical surface 

 such that the force acting on an electron is not dependent 

 on the electron taken. In general, the atoms ionized to so 

 great an extent will be comparatively few. In all our cases 

 of ionized atoms, it must be remembered that it is not only 

 the normal atom that is ionized ; an atom may have given 

 out several spectral lines before it becomes ionized. So a 





