Evaluation of NLO susceptibilities for l-threonine amino acid single crystals using anharmonic oscillator model

Three dimensional semi-classical anharmonic oscillator model proposed by Akitt has been used to evaluate the second order and electro-optic susceptibilities of l-threonine. As the ionic contribution to the optical non-linearity for the frequency range under study was negligible, the NLO parameters were calculated by taking the contribution of electronic polarization alone. The data presented here are in reasonable agreement with the experimental ones and the results have been discussed in detail.