Spectroscopy of jet-cooled Bi3

Area of Science:

• Molecular Spectroscopy
• Quantum Chemistry
• Physical Chemistry

Background:

• Bismuth clusters are of interest due to their unique electronic properties.
• Previous spectroscopic studies of bismuth clusters have yielded ambiguous assignments.
• Understanding the electronic structure of small bismuth molecules is crucial for materials science.

Purpose of the Study:

• To investigate the electronic states of jet-cooled bismuth trimer (Bi3) using high-resolution spectroscopy.
• To reassign previously observed spectral features and identify new electronic transitions.
• To characterize the spin-forbidden electronic transitions in Bi3.

Main Methods:

• Resonant two-photon ionization spectroscopy (RPI-S) was employed.
• Experiments were conducted on jet-cooled Bi3 molecules.
• Mass-resolved detection was utilized to ensure accurate spectral assignments.

Main Results:

• Two distinct electronic band systems of Bi3 were identified in the 9600–10 600 cm⁻¹ and 15 250–16 050 cm⁻¹ regions.
• A band system previously attributed to Bi4 was reassigned to Bi3.
• A new spin-forbidden band system, A′ 4A1″ ← X1 2E″ (E1/2 component), was characterized in the 9600–10 600 cm⁻¹ range.

Conclusions:

• The study provides a comprehensive analysis of the electronic states of Bi3.
• The reassignment of spectral features clarifies the understanding of bismuth cluster spectroscopy.
• The characterization of the spin-forbidden transition offers insights into the electronic structure and dynamics of Bi3.