ISSN:
1089-7550
Quelle:
AIP Digital Archive
Thema:
Physik
Notizen:
The crystal structure of synthetic BeO, bromellite, has been determined at several pressures to 5.0 GPa and several temperatures to 1183 K. The single variable atomic-positional parameter, z of oxygen, does not vary significantly with pressure, but does undergo a small increase with temperature. The hexagonal axial ratio c/a is constant with pressure, but decreases slightly from 1.624±0.001 to 1.623±0.001 between 300 and 1183 K. The observed crystal bulk modulus is 212±3 GPa, if K' is assumed to be 4. The bulk modulus of the beryllium tetrahedron in BeO is 210 GPa, identical to that of the crystal, and close to the value observed for beryllium tetrahedra in other beryllium minerals. The average volume thermal expansivity of the BeO beryllium tetrahedron between 298 and 1183 K is 2.5±0.2×10−5 K−1, compared to 2.66±0.10×10−5 K−1 for the crystal.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.336756
