Synthesis, Structural Characterization, and SHG behavior of a Lanthanum/β-D-fructose-based Metal Organic Framework

Interest in non-centrosymmetric crystalline materials exhibiting second harmonic genera-tion (SHG) has increased due to their potential applications in optical sensing and bio-sensing. Saccharide-based metal complexes are particularly attractive systems, as chiral sugars can promote non-centrosymmetric crystal packing. In this work, a new lantha-num–β-D-fructose compound, [La(C₆H₁₂O₆)(H₂O)₅]Cl₃ (LaFRUCl), was synthesized by a simple and low-cost method and characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group P2₁2₁2₁ and consists of infinite (La³⁺–fructose)ₙ chains extending along the [001] direction, forming a one-dimensional metal–organic framework. The nonlinear optical response was evaluated using the Kurtz–Perry powder technique with a Nd:YAG laser (1064 nm) and compared to a sucrose ref-erence. The measured SHG efficiency is comparable to that of previously reported alkaline earth metal–sugar analogues. While the SHG emission is significant, evaluation of the compound’s structural stability under aqueous or physiological conditions would be re-quired before considering biological applications.