Investigating in great detail the polarization dependence of the first-order Raman spectrum of -AlPO4 (berlinite), we discuss the experimental results in terms of first-order (quartzlike) and folded-zone frequencies. We identify all Raman-active modes predicted by group-theory arguments and find, in many cases, a small renormalization of experimental values through the isoelectronic sequence -SiO2, -SiO2, -AlPO4. This demonstrates a strong molecular character which is well accounted for by a simple model calculation in which one links, progressively, three decoupled SiO4 tetrahedra to build a quartzlike unit cell. © 1991 The American Physical Society.
|Journal||Physical Review B|
|Publication status||Published - 1 Jan 1991|
Goullet, A., Pascual, J., Cusco, R., & Camassel, J. (1991). Polarization dependence of the first-order Raman spectrum of -AlPO4. Physical Review B, 44(18), 9936-9943. https://doi.org/10.1103/PhysRevB.44.9936