Journal of Research of the National Bureau of Standards
The phase equilibrium diagram for the system Nb2O5 - GeO2 has been determined experimentally, using the quenching technique and examining the samples by optical microscopy and x-ray powder diffractometry. The system contains one compound, 9Nb2O5 � GeO2, which melts incongruently at 1420 �C. A eutectic between this compound and GeO2 is located at about 97 mol percent GeO2 and 1090 �C . The system does not show liquid immiscibility, and it is concluded that the ionic field strength limit for two-liquid separation in the series of glass formers occurs with the Nb+5 cation.
J. Res. Nat. Bur. Stand. Sec. A: Phys. Ch., Vol. 70A, No. 1, p. 5
ABBYY FineReader 8.0
The Journal of Research of the National Institute of Standards and Technology is a publication of the U.S. Government. The papers are in the public domain and are not subject to copyright in the United States. However, please pay special attention to the