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| | Calcium germanate Basic information |
| | Calcium germanate Chemical Properties |
| | Calcium germanate Usage And Synthesis |
| Description | Calcium germanate can be formed by firing the
oxides together at about 750–800°C:
CaO + GeO2?CaGeO3
A single-crystal X-ray study indicates that the perovskite
form of CaGeO3 is orthorhombic (Pbnm) and isotypic
with GdFeO3. The cell dimensions are:
a = 5.2608 ? , b = 6.2688 ? , c = 7.4452 ? , V = 366.43?3,
Z = 4, dcalc = 5.17 g/cc. The crystal structure is close to
that of SmAlO3. Although the unit cell of CaGeO3 is
pseudocubic, the structure itself is very distorted
through the tilting and distortion of polyhedra. The
oxygen polyhedra are less tilted and less distorted
than those of other GdFeO3-type perovskites. | | Physical properties | By using a diamond anvil pressure cell coupled with
laser heating, Ca2GeO4 has been found to decompose
into the mixture Ca3Ge2O7 plus CaO at pressures greater
than 200 kbar and at about 1000°C. | | Uses | Ca2GeO4 has been tested as a host for lasers, using
Nd3+
as the activator. Large crystals of highly doped
Ca2GeO4:Cr4+
were grown by a top-seeded meltsolution
growth method. Absorption and emission
measurements for various crystal orientations have
been performed. |
| | Calcium germanate Preparation Products And Raw materials |
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