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Updated: Aug 7, 2026
Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Structural modulation of the dipolar-octupolar contributions to the NLO response in subphthalocyanines
Christian G Claessens1, David González-Rodríguez, Tomás Torres
1Departamento de Química Orgánica (C-I), Departamento de Física de Materiales (C-IV), Universidad Autónoma de Madrid, 28049-Madrid, Spain.
Abstract:
Second order nonlinear optical properties of a series of trinitrosubphthalocyanine (SubPc) isomers were studied experimentally by electric field induced second harmonic (EFISH) generation and hyper Rayleigh scattering (HRS). These experimental values were compared to the ones obtained theoretically employing both sum over states (SOS) and finite field (FF) methods. From these studies, it was shown that the dipolar contributions to the beta tensor are very much dependent on the substitution pattern at the periphery of the subphthalocyanine macrocycle, whereas the octupolar contributions remain mostly unchanged. Consequently, it was deduced that SubPc is extremely well suited for the decoupling of octupolar and dipolar contribution to the NLO response.
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