Second-order non-linear optical response in LB films for the metal complexes

摘要

The complexes with long alkyl chains ([Fe(C-16-trz)(3)](ClO4)(2))(n) (1), [Fe(C-15-BPT)(2)(NCS)(2)] (2), [Fe(C-16-salen)Cl] (3), [Fe(C-16-salmmen)Cl] (4), K[Fe(C-16-salen)(CN)(2)] (S), K[Fe(C-16-salmmen)(CN)(2)] (6), Na[Fe(C-16-salmmen)(CN)(2)] (7), [Mn(C-16-salen)Cl] (8), [Ni(C-16-salen)] (9), [Cu(C-16-salen)] (10) were synthesized (C-16-trz = 4-hexadecyl-1,2,4-triazole, C-15-BPT = N-(3,5-di-2-pyridinyl-4H-1,2,4-triazol-4-yl)-hexadecanecarboxamide, C-16-salen = N,N-bis[4-(hexadecyloxy)salicylidene]ethylenediamine, C-16-salmmen = N,N'-bis[4-(hexadecyloxy)salicylidene]-1,2-diaminopropane). Langmuir-Blodgett (LB) films of compounds 1-10 were prepared (Scheme 1). The transfers of the molecules from onto the gas-water surface to glass substrate were confirmed by UV-Vis spectra. The second harmonic generation (SHG) were estimated for the LB films formed by the metal complexes. The SHG was observed for the complexes with the long alkyl chains in LB film. The order of the intensity for the SHG related with the number of unpaired d electrons or the d electron configurations.