Modeling Surface-Enhanced Raman Scattering of Au-Pyrazine and Au-Pyrazine-Au Nanorod Dimer Systems with the TD-DFTB Method DOI
Sajal Kumar Giri, George C. Schatz

The Journal of Physical Chemistry C, Год журнала: 2024, Номер 128(45), С. 19270 - 19279

Опубликована: Ноя. 1, 2024

This study investigates Raman scattering from a pyrazine molecule adsorbed on gold nanorod surfaces using the time-dependent density functional tight-binding (TD-DFTB) method. We analyze surface-enhanced (SERS) for two configurations: one where is single forming Au-pyrazine complex, and another it forms nanojunction Au-pyrazine-Au dimer system. These configurations offer distinct chemical environments different local field enhancements, with systems generating enhanced hotspot regions at junctions. present results structures, variable nanogap sizes that lead to shifts in plasmon energies. The identifies contributions SERS enhancements chemical, electromagnetic, resonance charge transfer mechanisms. Our show mechanism provides enhancement factors range of 102–103, while electromagnetic are order 104–106 monomer 106–108 structures. Charge resonances 102–103 range, depending energy relative energy. demonstrate all length 5.3 nm width 0.52 nm, containing 121 atoms.

Язык: Английский

Laser pulse induced second- and third-harmonic generation of gold nanorods with real-time time-dependent density functional tight binding (RT-TDDFTB) method DOI
Sajal Kumar Giri, George C. Schatz

The Journal of Chemical Physics, Год журнала: 2024, Номер 161(4)

Опубликована: Июль 23, 2024

In this study, we investigate second- and third-harmonic generation processes in Au nanorod systems using the real-time time-dependent density functional tight binding method. Our study focuses on computation of nonlinear signals based time dependent dipole response induced by linearly polarized laser pulses interacting with nanoparticles. We systematically explore influence various parameters, including pump intensity, duration, frequency, polarization directions, harmonic generation. demonstrate all results dimer arranged end-to-end configurations, disrupting spatial symmetry regular single is crucial for second-harmonic processes. Furthermore, impact lengths, which lead to variable plasmon energies, generation, estimates polarizabilities hyper-polarizabilities are provided.

Язык: Английский

Процитировано

3
Modeling Surface-Enhanced Raman Scattering of Au-Pyrazine and Au-Pyrazine-Au Nanorod Dimer Systems with the TD-DFTB Method DOI
Sajal Kumar Giri, George C. Schatz

The Journal of Physical Chemistry C, Год журнала: 2024, Номер 128(45), С. 19270 - 19279

Опубликована: Ноя. 1, 2024

This study investigates Raman scattering from a pyrazine molecule adsorbed on gold nanorod surfaces using the time-dependent density functional tight-binding (TD-DFTB) method. We analyze surface-enhanced (SERS) for two configurations: one where is single forming Au-pyrazine complex, and another it forms nanojunction Au-pyrazine-Au dimer system. These configurations offer distinct chemical environments different local field enhancements, with systems generating enhanced hotspot regions at junctions. present results structures, variable nanogap sizes that lead to shifts in plasmon energies. The identifies contributions SERS enhancements chemical, electromagnetic, resonance charge transfer mechanisms. Our show mechanism provides enhancement factors range of 102–103, while electromagnetic are order 104–106 monomer 106–108 structures. Charge resonances 102–103 range, depending energy relative energy. demonstrate all length 5.3 nm width 0.52 nm, containing 121 atoms.

Язык: Английский

Процитировано

2