Structure and the properties of V/sub 2/O/sub 5/-B/sub 2/O/sub 3/-Al/sub 2/O/sub 3/ glass system

The boron-oxygen structural configuration in glasses of the ternary system V/sub 2/O/sub 5/-B/sub 2/O/sub 3/-Al/sub 2/O/sub 3/ have been investigated by employing the B/sup 11/ nuclear magnetic resonance (NMR) techniques. The B/sup 11/NMR spectra from the glasses exhibit both broad resonance line characteristic of BO/sub 3/ units with three bridging oxygens and narrow resonance line due to the borons in four coordinated to oxygens. The fraction N/sub 4/ of borons in BO/sub 4/ units in the glasses is small in values, indicating that the formation of the boron coordinated to four oxygen atoms is not favoured in this glass system.