Phonon calculations on microwave dielectric material La(Mg1/2,Ti1/2)O3:Density-Functional Perturbation Theory Study

• Main Authors: Way-Chung Lee, 李維崇
• Other Authors: 林諭男
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/53177608596561991225

碩士 === 淡江大學 === 物理學系碩士班 === 96 === We use first-principles to begin the simulation on the microwave dielectric material La(Mg1/2,Ti1/2)O3. In our calculations, we use the Density-Functional Perturbation Theory and linear response method to get the phonons at Γ point. And then, we make a few experimental observations like Raman spectrum and FTIR spectrum on the microwave dielectric material La(Mg1/2,Ti1/2)O3. According to our calculations, the calculated eigenvalues and corresponding eigenvectors of each vibration mode at Γ point provide a great help on assignment of our experimental observations. Finally, we use the Lorentz model to study the relation between vibration modes and dielectric properties on the microwave dielectric material La(Mg1/2,Ti1/2)O3.