LaseRitz: Far-Infrared Laser Line Assignment and Prediction by the Ritz Combination Principle, with Application to...

Area of Science:

• Molecular spectroscopy
• Quantum optics
• Computational chemistry

Background:

• Far-infrared laser (FIRL) spectroscopy is crucial for understanding molecular energy levels.
• Previous methods for assigning FIRL transitions were often line-by-line and less systematic.
• Accurate prediction of FIRL transitions requires comprehensive molecular data.

Purpose of the Study:

• To develop and describe the LaseRitz program for systematic assignment and prediction of FIRL transitions.
• To identify new FIRL lines for methanol (CH3OH) and hydrazine (N2H4) using optical pumping.
• To provide a rigorous and global approach for calculating FIRL wavenumbers.

Main Methods:

• Inputting molecular energy levels from infrared (IR) and FIR ground state spectra into the LaseRitz program.
• Scanning the data for IR matches with known laser pump lines (e.g., CO2, N2O).
• Generating a table of possible FIRL lines based on molecular selection rules and wavenumber range.

Main Results:

• The LaseRitz program identified three likely new FIRL assignments for methanol (CH3OH).
• Assignments were found for 14 new FIRL transition systems and verified for five others in hydrazine (N2H4).
• Comprehensive lists of potential FIRL lines for CH3OH and N2H4 were generated and made available.

Conclusions:

• The LaseRitz program offers a more global and rigorous method for FIRL transition prediction compared to previous studies.
• The program enables the calculation of FIRL wavenumbers to spectroscopic accuracy.
• This systematic approach enhances the discovery and verification of FIRL transitions for various molecules.