The Influence of Different Elements on the Colour and Magnetic Susceptibility of Glass. Part I. Iron

JSGT 1954 V38 T057-T083

By means of a large number of transmission measurements of different kinds of glasses in the ultra-violet, visible and infra-red region the positions of the iron ions in the network of these glasses has been investigated. From a thorough analysis of the results in the ultra-violet region for glasses with comparative low iron contents, it is concluded that the ferric ions are found only in network-forming positions. From measurements in the near infra-red, where there is a region of absorption at 1·2 μm. due to the ferrous ions, and in the ultra-violet at 280 and 290 µm, before and after solarisation, it is established that the ferrous ions must also take network-forming positions. By means of magnetic susceptibility measurements the ratio of the ferrous and ferric ions in the investigated glasses were determined. Though the magnetic measurements do not give any information about the positions of the ferrous and ferric ions in glass, nevertheless it is still possible to conclude, by analogy with the cobalt-containing glasses investigated, that the bonding of the ferrous and ferric ions must be mainly ionic.

J. De Jong