The infrared (400-1200 cm(-1)) and Raman (200-1150 cm( 1)) spectra are repo
rted for the new AO(3)-BaF2-RF glasses where A is molybdenum or tungsten an
d RF is the alkali fluoride LiF, NaF and mixed LiF-NaF respectively. The ob
served absorption bands of each glass series were assigned to their vibrati
onal modes. This study has shown that structural units formed in these glas
ses include [MoO4] and [WO4] tetrahedra, [MoO6], [WO6], [MoF6] and [WF6] oc
tahedra groups. (C) 1999 Kluwer Academic Publishers.