Glasses Technology

Zhang, Lipeng?Wang, Paul W.

The effect of chlorine on the structure of AlF//3/YF//3-based fluoride glasses was studied by XPS. The changes in the bonding state of cations with increase of chlorine content were all investigated by measuring the composition- dependent changes in the relative concentration and binding energy of related cations. It was proposed that the chlorine replaces the bridging fluorine by which the [AlF//n] and [YF//m] polyhedra are connected and result in the formation of [AlF//n//- //uCl//u] and [YF//m//-//vCl//v] polyhedra. In the low BaCl//2 content region ( less than 6 mol%), as many chlorine as possible attack [AlF//n] and [YF//m] polyhedra, and with the increase of chlorine content, they replace more fluorines in [YF//m] polyhedra, while the number of chlorines in [AlF//n//-//uCl//u] polyhedra remains a low constant value. In the high BaCl//2 content region ( greater than 6 mol%), the chlorines replace more fluorines in the already formed [AlF//n//-//uCl//u] polyhedra and do not attack other [AlF//n] polyhedra, while the composition of [YF//m//- //vCl//v] polyhedra do