The bond dissociation energy of VO measured by resonant three-photon ionization spectroscopy

Merriles, DM; Sevy, A; Nielson, C; Morse, MD / JOURNAL OF CHEMICAL PHYSICS (2020) / DOI: https://doi.org/10.1063/5.0014006

Overview

The predissociation threshold of VO has been measured using resonant three-photon ionization (R3PI) spectroscopy. Given the high density of electronic states in the molecule, it is argued that the molecule dissociates rapidly as soon as the thermochemical bond dissociation energy (BDE) is exceeded, allowing the measured predissociation threshold to be assigned as the BDE. This is the first time a BDE has been measured using the R3PI method. The first photon is provided by an optical parametric oscillator (OPO) laser that promotes VO into a high-energy, discrete vibronic state. A tunable dye la

Key Points

• 1. Excitation scheme & wavelength design
• 2. Pulse energy and delay tuning
• 3. Balancing selectivity and ionization efficiency

Design & Function

• Design: Optimize multistep resonance scheme and optics
• Function: Evaluate ion signal, S/N and resolution
• Feature: Parameter optimization for wavelength/energy/delays

Mini Glossary

• R3PI — Resonance-enhanced three-photon ionization
• REMPI — Resonance-enhanced multiphoton ionization

References

1. JOURNAL OF CHEMICAL PHYSICS (2020). DOI: https://doi.org/10.1063/5.0014006

The bond dissociation energy of VO measured by resonant three-photon ionization spectroscopy

Merriles, DM; Sevy, A; Nielson, C; Morse, MD / JOURNAL OF CHEMICAL PHYSICS (2020) / DOI: https://doi.org/10.1063/5.0014006

概要 / Overview

共鳴三光子イオン化（R3PI）による高感度計測。段階的共鳴状態の設計と光学系の調整で、高S/Nのイオン信号を実現。

ここがポイント / Key Points

• 1. 励起スキーム/波長設計
• 2. パルスエネルギー・遅延チューニング
• 3. 選択性とイオン化効率の両立

設計と機能 / Design & Function

• 設計：多段励起（選択則・中間準位）と光学系の最適化
• 機能：イオン信号・S/N・分解能の評価
• 特長：波長/エネルギー/遅延のパラメトリック最適化

用語ミニ解説 / Mini Glossary

• R3PI：共鳴三光子イオン化（Resonance-enhanced three-photon ionization）
• REMPI：共鳴多光子イオン化（Resonance-enhanced multiphoton ionization）

参考文献 / References

1. JOURNAL OF CHEMICAL PHYSICS (2020). DOI: https://doi.org/10.1063/5.0014006