Unveiling the Superior Optical Properties of Novel Melamine-Based Nonlinear Optical Material with Strong Second-Harmonic Generation and Giant Optical Anisotropy.
Small
; 19(28): e2301756, 2023 Jul.
Article
in En
| MEDLINE
| ID: mdl-36970809
ABSTRACT
Two melamine-based metal halides, (C3 N6 H7 )(C3 N6 H6 )HgCl3 (I) and (C3 N6 H7 )3 HgCl5 (II), are synthesized by incorporating the heavy d10 cation, Hg2+ , and the halide anion, Cl- . The noncentrosymmetric structure of I results from two unique attributes large asymmetric secondary building units produced by direct covalent coordination of melamine to Hg2+ and a small dihedral angle between melamine molecules. The former makes inorganic modules locally acentric, while the latter prevents planar organic groups from forming deleterious antiparallel arrangement. The unique coordination in I results in an enlarged band gap of 4.40 eV. Due to the large polarizability of the heavy Hg2+ cation and the π-conjugated system of melamine, I exhibits a strong second-harmonic generation efficiency of 5 × KH2 PO4 , larger than any reported melamine-based nonlinear optical materials to date. Density functional theory calculations indicate that I possesses giant optical anisotropy, with a birefringence of 0.246@1064 nm.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Small
Journal subject:
ENGENHARIA BIOMEDICA
Year:
2023
Type:
Article