| Autor: |
Legat T; Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium. stijn.vancleuvenbergen@kuleuven.be.; Sustainable Materials Lab, Department of Chemical Engineering, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium., Mairesse F; Theoretical Chemistry Laboratory, Unit of Theoretical and Structural Physical Chemistry, NISM (Namur Institute of Structured Matter), University of Namur (UNamur), B-5000 Namur, Belgium. benoit.champagne@unamur.be., Dok AR; Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium. stijn.vancleuvenbergen@kuleuven.be., de Coene Y; Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Celestijnlaan 200D, 3001 Heverlee, Belgium., Thielemans W; Sustainable Materials Lab, Department of Chemical Engineering, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium., Champagne B; Theoretical Chemistry Laboratory, Unit of Theoretical and Structural Physical Chemistry, NISM (Namur Institute of Structured Matter), University of Namur (UNamur), B-5000 Namur, Belgium. benoit.champagne@unamur.be., Van Cleuvenbergen S; Molecular Imaging and Photonics, Department of Chemistry, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium. stijn.vancleuvenbergen@kuleuven.be. |
| Abstrakt: |
Cellulose nanocrystals (CNCs) have attracted considerable interest due to their optical properties, though their nonlinear optical behavior remains largely unexplored. In this paper, we investigate the second-order nonlinear optical (SONLO) response of CNCs through both experimental and theoretical investigations. Hyper-Rayleigh scattering (HRS) experiments revealed values comparable to well-known nonlinear optical biomaterials, such as collagen, and on par with inorganic reference materials like KDP. The strong response in CNCs can be attributed to the well-ordered structure of the cellulose chains, which enhances the overall susceptibility of the nanoparticles. Quantum chemical modeling using density functional theory (DFT) was employed to simulate the molecular hyperpolarizability of CNCs. The study reduced the complex first hyperpolarizability tensor of the CNCs to two key components, β zzz and β zyy . An electrostatic model was applied to account for the CNCs' shape and dielectric properties, leading to strong agreement with the experimental data. Our findings highlight the potential of CNCs for optoelectronic applications and provide valuable insights for characterizing CNC-based mesomaterials through two-photon microscopy. |
