Influence of Light on Paramagnetic Susceptibility

Abstract

SELWOOD¹ has recently published the result of his investigation on the influence of the absorption of light on the paramagnetic susceptibility of certain solutions, in which he fails to confirm our observation of the increase of susceptibility under such conditions. He finds, in agreement with Gorter's observation, that there is a gradual diminution of susceptibility of the solution which can be attributed to a rise of its temperature, due to absorption of light. The method used by him is that due to Decker, in which a test piece of glass of nearly the same susceptibility as the paramagnetic solution is suspended from a torsion head between the pole pieces of an electromagnet. The sensitiveness of his apparatus is claimed to be 0.005 per cent.