Triatomic molecule

A molecule composed of three atoms

A triatomic molecule is a molecule composed of three atoms, which may or may not be of the same chemical element. Triatomic molecules can be linear or nonlinear in shape.

Examples

Carbon dioxide

3D model of a carbon dioxide molecule

Carbon dioxide (CO_) is a linear triatomic molecule consisting of one carbon atom and two oxygen atoms. It is a significant component of the Earth's atmosphere and is involved in the carbon cycle. Carbon dioxide is a greenhouse gas and plays a crucial role in photosynthesis.

Ozone

3D model of an ozone molecule

Ozone (O_) is a nonlinear triatomic molecule composed of three oxygen atoms. It is found in the Earth's stratosphere and forms the ozone layer, which absorbs most of the Sun's harmful ultraviolet radiation. Ozone is also present at ground level as a pollutant.

Trihydrogen cation

3D model of a trihydrogen cation

The trihydrogen cation (H__) is a positively charged ion consisting of three hydrogen atoms. It is an important species in interstellar space and plays a role in the chemistry of star formation.

Properties

Triatomic molecules can exhibit a variety of properties depending on their structure and composition. Linear triatomic molecules, such as carbon dioxide, have a straight-line geometry, while nonlinear molecules, like ozone, have a bent shape. These structural differences affect their vibrational and rotational spectra.

Applications

Triatomic molecules are important in various fields of science and technology. Carbon dioxide is used in carbonated beverages, fire extinguishers, and as a refrigerant. Ozone is used in water purification and air purification systems. The trihydrogen cation is studied in astrophysics and quantum chemistry.

Related pages

• Diatomic molecule
• Polyatomic molecule
• Molecular geometry

References

• Atkins, P., & de Paula, J. (2006). Physical Chemistry. Oxford University Press.
• Herzberg, G. (1966). Molecular Spectra and Molecular Structure. Van Nostrand Reinhold.

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  Carbon dioxide molecule
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  Ozone molecule
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  Trihydrogen cation