Work

Tuning Photoluminescence and Emission Polarization in Metal–Curcumin Complexes via Magnetic Fields

Year: 2026

Type: article

Abstract: Curcumin complexes with Zn-(II), Pb-(II), and Ca-(II) were synthesized and spectroscopically characterized, with emphasis on magnetic field modulation of photoluminescence and emission polarization. Raman and FTIR analyses confirm coordination through the enolized β-diketone moiety. UV-Vis absorption and photoluminescence spectra exhibit red shifts, 426-432 and 525-534 nm, respectively, indicating metal-ligand interactions and charge-transfer contributions. Vibronic line shape analysis reveals changes in the electronic gap, electron-vibrational mode coupling, and spectral line width, with significant narrowing for the Zn-(II) complex, consistent with increased molecular rigidity. Measurements using the emission ellipsometry technique demonstrate that an external magnetic field modulates both the intensity and polarization of the emitted light of curcumin in a coordination-dependent manner, with the strongest response observed for the Zn-(II) complex. These results show that metal coordination combined with magnetic fields provides an effective strategy to tune photoluminescence and emission polarization in curcumin-based systems, highlighting their potential for photonic and magneto-optical applications.

Source: ACS Omega

DOI: 10.1021/acsomega.6c03000