Which molecule has not yet been detected in the atmospheres of exoplanets?

Question

Quizplus · Accepted Answer

Methane, carbon dioxide, and water have all been detected in the atmospheres of exoplanets, but the detection of oxygen has been elusive so far. This is largely due to the fact that oxygen is a highly reactive molecule and tends to quickly bond with other elements, making it difficult to detect on its own. It is thought that the presence of oxygen in an exoplanet's atmosphere could be a potential indicator of the presence of life, making it an important target for future exoplanet observations.

Which Molecule Has Not Yet Been Detected in the Atmospheres