Spectral characterization of a non-centrosymmetric organic compound: D-(-)-alanine

The crystal growth of D-(-)-alanine (1), a non-centrosymmetric solid is reported. The structure was optimized computationally at the B3LYP/6-311G** level and the vibrational frequencies were calculated. These were compared with the frequencies observed in the Raman and IR spectra recorded. The CD spectral measurements unambiguously confirmed that the compound (1) is D-(-)-alanine. Second harmonic generation (SHG) conversion efficiency is about 23% of that of the standard KDP crystals. Optical studies showed that the crystal is transparent in the UV-Vis and NIR region. The compound may have possible applications in non-linear optics.