Infrared and Raman study of lattice vibrations of CuAlSe2 single crystals Original Research Article

The Infrared and Raman study of lattice vibrations of the chalcopyrite compound CuAlSe2 with a complete assignment of the lattice vibrational modes is reported. Each two modes of E symmetry and one mode of B2 symmetry have been found in the high frequency (from 250 to 400 cm−1), medium frequency (from 160 to 200 cm−1) and low frequency (from 60 to 120 cm−1) region of the spectrum. Violations of the selection rules of infrared activity observed for the B1 symmetry mode of highest energy as well as the E symmetry mode of lowest energy may indicate a distortion of the crystal lattice.