High-Resolution Laser Spectroscopy of YbCl: The B(2)Sigma(+)-X(2)Sigma(+) Transition

Area of Science:

• Molecular Spectroscopy
• Quantum Chemistry
• Atomic Physics

Background:

• The B(2)Sigma(+)-X(2)Sigma(+) transition in Ytterbium Chloride (YbCl) is crucial for understanding molecular electronic structure.
• Previous studies have hinted at interactions between excited electronic states in YbCl.

Purpose of the Study:

• To obtain high-resolution laser excitation spectra for the B(2)Sigma(+)-X(2)Sigma(+) transition of YbCl.
• To perform rotational analysis on specific isotopomers of YbCl.
• To investigate the interaction between the B(2)Sigma(+) and A(2)Pi(1/2) excited states.

Main Methods:

• High-resolution laser excitation spectroscopy.
• Rotational analysis of spectral bands.
• Isotopic substitution using (174)Yb(35)Cl and (172)Yb(35)Cl.

Main Results:

• Detailed spectral data for the 0-0, 1-1, and 0-1 bands of the B(2)Sigma(+)-X(2)Sigma(+) transition were obtained.
• Rotational analysis yielded precise molecular constants for the B(2)Sigma(+) state, including B(e)=0.097552(5) cm(-1) and R(e)=2.43623(6) Å.
• The spin-rotation constant (gamma) for the B(2)Sigma(+) state was determined to be -2.1655(6)x10(-4) cm(-1).

Conclusions:

• The B(2)Sigma(+) and A(2)Pi(1/2) states of YbCl form a unique perturber pair.
• This interaction arises from the 6psigma and 6ppi orbitals of the Yb(+) ion.
• The results provide valuable data for theoretical models of molecular electronic structure and interactions.