A three-dimensional noncentrosymmetric zinc-4,4′,4′'-nitrilotribenzoate structure exhibiting second-harmonic generation responses.

A three-dimensional structure [Zn(H-ntb)] n (1) constructed from the tetrahedrally coordinated Zn(II) atoms and 4,4′,4′'-nitrilotribenzoate ligands was presented. Compound 1 exhibits a phase-matchable second-harmonic-generation response of 1.2 times that of KDP. • A noncentrosymmetric coordination network. • A compound constructed from the 4,4′,4′'-nitrilotribenzoate. • Helical chains based on the 4,4′,4′'-nitrilotribenzoate and [ZnO 4 ] tetrahedrons. • A 3D zinc compound exhibits a large SHG response. A coordination polymer [Zn(H-ntb)] n (1) based on the tritopic carboxylate linker of 4,4′,4′'-nitrilotribenzoate (H 3 -ntb) was reported here. Compound 1 crystallizes in a polar space group of Pca 2 1 and contains two-dimensional layers formed from the left- and right-handed helical chains pillared by the benzoate moieties to give a three-dimensional structure. The present compound 1 features a noncentrosymmetric structure and displays a strong phase-matchable second-harmonic-generation (SHG) response of 1.2 times that of potassium dihydrogen phosphate (KDP). The inherent polarity of the 4,4′,4′'-nitrilotribenzoate and distortive [ZnO 4 ] tetrahedrons as well as the asymmetric arrangement of the building blocks are responsible for the SHG activity for 1. [ABSTRACT FROM AUTHOR]