Projects / Programmes
Influence of the crystal structure modifications of high-permittivity microwave materials on dielectric properties
Code |
Science |
Field |
Subfield |
1.04.03 |
Natural sciences and mathematics |
Chemistry |
Inorganic chemistry |
Code |
Science |
Field |
P260 |
Natural sciences and mathematics |
Condensed matter: electronic structure, electrical, magnetic and optical properties, supraconductors, magnetic resonance, relaxation, spectroscopy |
P250 |
Natural sciences and mathematics |
Condensed matter: structure, thermal and mechanical properties, crystallography, phase equilibria |
microwave ceramics, dielectrics, crystal structure, dielectric losses, temperature coefficient, perovskites, pyrochlore
Researchers (1)
no. |
Code |
Name and surname |
Research area |
Role |
Period |
No. of publicationsNo. of publications |
1. |
11991 |
PhD Matjaž Valant |
Materials science and technology |
Head |
1998 - 2001 |
609 |
Organisations (1)
no. |
Code |
Research organisation |
City |
Registration number |
No. of publicationsNo. of publications |
1. |
0106 |
Jožef Stefan Institute |
Ljubljana |
5051606000 |
91,415 |
Abstract
The aim of the research project is to explain the influence of the crystal structure modifications of Ba6-xR8+2/3xTi18O54 (R=La-Gd) solid solutions on the basic polarization mechanisms. In the first part of the work investigations will be focused mainly on the crystal structure determinations of solid solutions containing various rare earth elements and different compositions along the solid solubility region. The influence of temperature on crystal structure and dielectric properties will be studied as well. A structural feature that will be closely examined is the corner-sharing TiO6 octahedral network. Presumably, it is essentially responsible for the variations in the anharmonicity of the crystal structure and consequently, for the variations in the dielectric losses and temperature coefficient of the permittivity. Findings obtained through the work on that research project will be generalized on the related crystal structures (pyrochlores, perovskites) that consist corner-sharing TiO6 octahedral network. Understanding of the fundamental structural mechanisms will enable more efficient and planned development of new high-permittivity microwave materials.