Ten articles have been published which contain extensive databases of empirical  rovibrational energy levels, based on spectral features measured under high resolution, for ​the most abundant twelve isotopologues of carbon dioxide.​​ 

The variation in the CO₂ content of Earth's atmosphere over time is one of its key characteristics. A detailed understanding of CO₂'s spectroscopic features, particularly the line center positions, both with and without collisional effects, is crucial for determining the total amount and distribution of this molecule in the atmosphere. This data also aids in understanding the role of CO₂ in various environmental issues, such as climate change and the radiative balance of our atmosphere. The industrial revolution has significantly impacted climate change, with the well-documented increase in CO₂ concentration over the last century being largely due to human activities. Approximately 98.45% of carbon dioxide molecules in Earth's atmosphere are in the form of the ¹⁶O¹²C¹⁶O isotopologue, making it the most important isotopologue for study.

Carbon dioxide also plays a critical role in astronomical research, ranging from stellar studies to the exploration of planetary atmospheres. In our solar system, CO₂ is the major constituent of the atmospheres of Mars and Venus, influencing their radiative balances. The detection and analysis of CO₂ absorption features in exoplanetary spectra provide insights into the atmospheric composition, pressure, and temperature profiles of distant worlds. CO₂ was among the first molecules detected in exoplanet atmospheres, with recent observations made using the James Webb Space Telescope. In the interstellar medium's dense molecular clouds, CO₂ serves as an important tracer of the physical and chemical conditions that govern the birth of new stars. Emissions from the bending states of CO₂ isotopologues in the far infrared offer valuable information on the temperature, density, and kinematics of these star-forming regions.

Monitoring the CO₂ content of Earth's atmosphere is a significant activity aimed at tracking the carbon levels in increasing detail. Missions like NASA’s OCO-2 and OCO-3 satellites, as well as ESA’s planned CO2M satellite constellation, require precise laboratory spectroscopy results to interpret their data. Similar accuracy is essential for ground-based spectroscopic experiments, such as TCCON (Total Carbon Column Observing Network). The most important outcomes of this study, obtained using the MARVEL code for twelve CO₂ isotopologues, include datasets of validated experimental transitions and empirical rovibrational energy levels. These data will contribute not only to future spectroscopic measurements of carbon dioxide but also to the refinement of theoretical and computational spectroscopic models and the enhancement of spectroscopic line-by-line databases, such as HITRAN23 and ExoMol.​

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