ABSORPTION OF IRON AND WATER IN THE NA2O-CAO-MGO-SIO2 GLASSES - I - SEPARATION OF FERROUS AND HYDROXYL SPECTRA IN THE NEAR IR REGION

A number of 13Na(2)O-10CaO-6MgO-71SiO(2) glasses doped with iron were melted in gas and electric furnaces using for batching both natural ma terials that are usually used in glass industry, and high purity chemi cals. The concentration of Fe2O3 in the glasses was varied from 5 x 10 (-4) to 0.9 wt%. Absorption spectra of water and ferrous ions for the spectral region 3000-1000 nm (3300-10 000 cm(-1)) were separately dete rmined from experimental absorption spectra and tabulated. An absorpti on band for the ferrous ion was observed in the region of 2985 nm (335 0 cm(-1)) which, to our knowledge, has not been reported, A simple alg orithm was developed to describe absorption of water and iron in each glass and to simulate the spectra in both pure and iron doped silicate glasses. Only two parameters are necessary for spectra simulation; bo th can be determined from experimental absorption spectra. (C) 1997 El sevier Science B.V.