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Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
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External electric field modulated second-order nonlinear optical response and visible transparency in
1Department of Physics, Deen Dayal Upadhyaya Gorakhpur University, Civil Lines, Gorakhpur, 273009, India. aks.ddugu@gmail.com.
Journal of Molecular Modeling
|January 7, 2021
Summary
External electric fields (EEFs) significantly enhance the nonlinear optical (NLO) response of hexalithiobenzene (C6Li6). This research demonstrates EEFs as a method to improve NLO materials and potential optical device applications.
Area of Science:
- Computational Chemistry
- Materials Science
- Quantum Chemistry
Background:
- The second-order nonlinear optical (NLO) response of hexalithiobenzene (C6Li6) is poor due to its low first mean hyperpolarizability.
- External electric fields (EEFs) can tune molecular properties by aligning molecules.
Purpose of the Study:
- To investigate the impact of EEFs on the structural, electronic, and NLO properties of C6Li6.
- To explore the potential of EEFs in enhancing the NLO response of C6Li6 for material design.
Main Methods:
- Density functional theory (DFT) approach was employed.
- Analysis of structural, electronic, and NLO properties under varying EEFs.
Main Results:
- C6Li6 remains planar with minor bond length adjustments and increased stability under EEFs.
- EEFs decrease the HOMO-LUMO energy gap, enhancing conductivity and reactivity.
- A significant enhancement of the first static hyperpolarizability was observed, reaching 3.4 × 10^4 a.u. at 50 × 10^-4 a.u. EEF.
- C6Li6 exhibits a tunable dipole moment linearly dependent on EEF strength.
Conclusions:
- EEFs are an effective strategy to significantly boost the second-order NLO responses of C6Li6.
- The enhanced NLO properties and visible transparency suggest potential applications for C6Li6 in optical devices.
- This study provides a pathway for designing novel NLO materials by utilizing external electric fields.
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