Laser Raman Spectrum of Triglycine Sulfate

Abstract

The laser Raman spectrum of ferroelectric triglycine sulfate has been determined by the use of an argon ion gas laser. The observed Raman lines are compared with reported assignments in the literature by Taurel¹ and Krishnan², Determination of depolarization ratio of the sulfate line at 980 cm^?1 shows that the Raman band is highly polarizable and the molecular vibration is totally symmetrical v₁.

The role played by the glycine groups in the spontaneous polarization and its reversal can be indirectly confirmed by Raman spectrum of TGS. Interpretation of the Raman spectrum indicates that the SO₄ groups do not have tetrahedral symmetry at roan temperature. Ferroelectric behavior of TGS is attributed to the glycine groups.