Description
Bismuth germanate is
a cubic crystal with the formula, Bi4Ge3O12. It has the
“evlitine” structure. A less common composition is
Bi12GeO20 .
The unit cell consists of three GeO3 tetraheda arranged
in a building block. These units are arranged in a cubic
close-packed structure as shown in the above diagram.
The crystal structure of tetrabismuth tris(germanate),
Bi4Ge3O12 (I3d, Z =4), is stable to at least 7.30 GPa, as
demonstrated by hydrostatic single-crystal XRD
measurements in a diamond anvil cell at room temperature.
Chemical Properties
white chips or powder(s), 99.99995% purity [ALF93]
Uses
Scintillator crystal in nuclear physics, high-energy physics, geology, and nuclear medical imaging applications including PET, X-ray CT and positron CT; in electromagnetic calorimeters.
Uses
Bismuth germanate is used in detectors in particle
physics, aerospace physics, nuclear medicine, geology
exploration, and other industries. Bismuth germanate
arrays are used for gamma pulse spectroscopy. BGO
crystals are also used in detectors for positron emission
tomography. Bismuth germanate has a high “electrooptic
coefficient” (3.3 pm/V for Bi12GeO20) making it
useful in nonlinear optics for building “Pockel cells”. It
can also be used for photorefractive elements useful in
the ultraviolet part of the electromagnetic spectrum.
Uses
Bismuth germanium oxide is used as an organic chemical synthesis intermediate.