Glasses with compositions (1-x)ZrF4-xLnF(3), 0.2 less than or equal to
x less than or equal to 0.4 and Ln = La or La, Eu have been synthesiz
ed and investigated using differential scanning calorimetry, X-ray dif
fraction, Raman scattering and Eu3+ optical spectroscopy. Single-phase
polycrystalline lanthanum fluorozirconates with Zr/Ln ratio equal to
1, 2 and 3 have been investigated using the same techniques for compar
ison. The crystalline phases LnZrF(7), LnZr(2)F(11), LT-LnZr(3)F(15) (
orthorhombic) and HT-LnZr(3)F(15) (trigonal) have been characterized i
n the recrystallized glasses and in samples spontaneously crystallized
from the melt. Another phase has also been observed but remains undef
ined, The Raman scattering spectra of the vitreous samples are related
to the vibration modes of [ZrF6] isolated octahedra, and of [ZrF7] an
d [ZrF8] structural units with bridging fluorine ions. The Eu3+ fluore
scence data are related to a predominant local environment of the lant
hanide ions in the glasses similar to that of the lanthanide in LnZrF(
7).