Three of his last research articles concerned detection of triatomic hydrogen and helium-3. The vibrational modes of a triatomic molecule can be determined in specific cases. The reduction of independent variables makes use of three properties of gas-phase, ground-state, triatomic molecules. Ozone, O is an example of a triatomic molecule with all atoms the same. After this researchers thought that active hydrogen could be the triatomic form. In chemistry, chloryl refers to a triatomic cation with chemical formula . Triatomic hydrogen will be formed during the neutralization of H. Ozone is a triatomic gas even more reactive than oxygen. Ozone (O) is a common triatomic homonuclear molecule. This linear, triatomic pseudohalogen is an easily condensed colorless gas. Other triatomic species [XY] can be similarly interpreted. Homonuclear triatomic molecules contain three of the same kind of atom. Triatomic hydrogen, H, is unstable and breaks up spontaneously. Triatomic hydrogen or H is an unstable triatomic molecule containing only hydrogen. Neutral triatomic hydrogen H can exist only in an excited form and is unstable.