In the theory calculation of lattice vibration, one acoustic and three optical branches were found to compose the phonon vibrating spectrum.Some isolated modes with frequencies lying outside the continuum branches wil...In the theory calculation of lattice vibration, one acoustic and three optical branches were found to compose the phonon vibrating spectrum.Some isolated modes with frequencies lying outside the continuum branches will arise under the defect states.These local model results in the sharp peaks in the infrared absorption and Raman spectra.From calculation of the infrared absorption,the local mode with the infrared activity is obtained in the infrared absorption spectrum of MX compounds.展开更多
文摘In the theory calculation of lattice vibration, one acoustic and three optical branches were found to compose the phonon vibrating spectrum.Some isolated modes with frequencies lying outside the continuum branches will arise under the defect states.These local model results in the sharp peaks in the infrared absorption and Raman spectra.From calculation of the infrared absorption,the local mode with the infrared activity is obtained in the infrared absorption spectrum of MX compounds.
