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Updated: Jun 11, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
The 480 nm system of KRb: 1 3Delta1, 4 1Sigma+, and 5 1Sigma+ states
Yonghoon Lee1, Youngjee Yoon, Adnan Muhammad
1Department of Chemistry, Mokpo National University, Jeonnam 534-729, Korea.
Abstract:
We have investigated the KRb 480 nm system by mass-resolved resonance enhanced two-photon ionization in a cold molecular beam. The 1 (3)Delta(1), 4 (1)Sigma(+), and 5 (1)Sigma(+) <-- X (1)Sigma(+) transitions have been identified. For the 1 (3)Delta(1) and 5 (1)Sigma(+) states, the electronic term values and vibrational constants are determined experimentally for the first time. Potential energy curves of the 4 (1)Sigma(+) and 5 (1)Sigma(+) states undergo multiple avoided crossings with nearby (1)Sigma(+) states in the observed spectral region. For the 4 (1)Sigma(+) state, a vibrational numbering of the experimentally observed levels is suggested. Anomalies in vibronic structures of the 4 (1)Sigma(+) and 5 (1)Sigma(+) states are understood by comparison with high-level ab initio calculations currently available. The avoided crossing energies are also experimentally estimated.
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