Nonlinear Optical Responses in One-Dimensional Zinc Thiocyanates Functionalized with Natural Amino Acids

Transparent crystals of Zn(SCN) 2 ( l -C 6 H 9 N 3 O 2 ) ( 1 ) and Zn(SCN)( l -C 5 H 8 NO 2 )(H 2 O) ( 2 ) were obtained using natural amino acids as linkers. The two compounds have one-dimensional structures that combine molecular and helical chiralities. They exhibit significant nonlinear optical responses that are phase matchable under 1064 nm laser irradiation. Notably, the second-harmonic generation efficiency of compound 2 (3.8 × KH 2 PO 4 ) surpasses those of previously reported metal thiocyanates functionalized with natural amino acids.