TheoReTS

TheoReTS predicts rovibrational spectra and generates isotopolog-specific line lists using first-principles variational methods for molecular spectroscopy and remote sensing applications.

Key Features:

• First-Principles Variational Approach: Uses a variational framework within the Born-Oppenheimer approximation to compute rovibrational line positions and absorption cross sections consistent with experiment.
• Isotopolog-Specific Analysis: Handles isotopic substitutions such as D2H2 and evaluates symmetry-breaking effects on infrared spectra.
• Normal-Mode Transformations: Employs normal-mode transformations to analyze changes in molecular vibrations and rotations under isotopic substitution.
• Ab Initio Potential and Dipole Surfaces: Utilizes ab initio potential energy surfaces and dipole moment surfaces for spectral calculations.
• Comprehensive Line Lists: Generates detailed line lists and predicted transition intensities across 0-4500 cm^-1.
• Temperature- and J-Specific Simulations: Simulates spectra at specified temperatures (e.g., 296 K) and rotational quantum numbers up to J = 38.

Scientific Applications:

• Remote Sensing Retrieval: Provides accurate line lists and intensities for detection of isotopic species in remote sensing studies.
• Spectroscopic Research: Supports analysis of vibrational and rotational characteristics to advance molecular spectroscopy investigations.
• Isotopic Analysis: Enables prediction of spectra for isotopologs to inform isotopic labeling and tracing studies.

Methodology:

First-principles variational methods within the Born-Oppenheimer approximation using a normal-mode approach and ab initio potential energy and dipole moment surfaces, accounting for symmetry-breaking due to isotopic substitutions.