Calcium germanate
- CAS No.
- Chemical Name:
- Calcium germanate
- Synonyms
- Calcium germanate
- CBNumber:
- CB24865948
- Molecular Formula:
- CaGeO3
- Molecular Weight:
- 160.7162
- MDL Number:
- MOL File:
- Mol file
Calcium germanate Chemical Properties,Uses,Production
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.