Change of Paramagnetic Susceptibility due to Absorption of Light

WE have already published in NATURE¹ a note giving the results of our observation on the change in susceptibility produced in paramagnetic solutions like that of chromic chloride, etc., due to light absorption. Following the suggestion of S. Kato, we had assumed that the absorption maxima at λ 4300, 6100 in a given solution of chromic chloride were due to the transition of the Cr⁺⁺⁺ion from the ⁴F' to ²G resp. ²H state. On the supposition that both in the initial and in the final state the magnetic moment of the ion is due only to the spin moments of the magnetic electrons, such transitions would be accompanied by diminution in the magnetic moment of the ion. We reported that the result of our observation indicated a diminution in the susceptibility of the chromic chloride solution and therefore was in agreement with our theoretical assumptions.