Description
Magnesium germanate can be formed by firing the
oxides together at about 900°C.
MgO + GeO2?MgGeO3
This salt has the perovskite structure. The lattice
parameters are: a = 4.9375 ?, c = 13.743 ?,
V = 290.15 ?
3. It occurs as the mineral, “majorite”,
with lattice parameters of: a = 11.051 ?, b = 11.051 ?,
c = 11.480 ?, α= β = γ = 90°.
MgGeO3 is polymorphic. It forms several types of
pyroxenes. Pyroxene is one of the important constituent
minerals of the earth’s crust and upper mantle.
, space group = I41/A.
There are four (4) magnesium germanates known as
shown in the following phase diagram of the system,
MgO–GeO2 where each compound can be obtained by
varying the MgO/GeO2 mol ratios before firing
(Fig. 5.55).
MgGeO3 is polymorphic. It forms several types of
pyroxenes. Pyroxene is one of the important constituent
minerals of the earth’s crust and upper mantle.
Uses
Magnesium germanate, when activated by manganese
has long been used in fluorescent lamps. The emission
spectrum of Mg4GeO6:0.01Mn
2+
has been found to
depend on the temperature of preparation.
