mehratomigen

Mehratomigen, or polyatomic, molecules are chemical species that consist of more than two atoms linked by covalent bonds. In German usage, the noun phrase is mehratomige Moleküle and the English equivalent is polyatomic molecules. By contrast, diatomic molecules contain only two atoms (for example O2, N2).

Most polyatomic molecules are held together by covalent bonds. Their three-dimensional shapes result from electron pair repulsion (VSEPR theory) and, in some cases, electron delocalization. The arrangement of atoms determines properties such as polarity and reactivity. Examples include water (H2O) with a bent shape and carbon dioxide (CO2) with a linear, nonpolar geometry.

Triatomic molecules include H2O, O3, and CO2; larger polyatomic molecules include methane (CH4) and ammonia (NH3). Organic chemistry features many larger polyatomic molecules such as ethanol (C2H5OH) or glucose (C6H12O6). The diversity of polyatomic structures enables a wide range of chemical behaviors and applications.

Polyatomic molecules occur across inorganic, organic, atmospheric, and biological chemistry. Their properties influence phase behavior, spectroscopy, acid-base reactivity, and catalysis. Nomenclature often reflects molecular geometry and functional groups, while many polyatomic species can form ions (polyatomic ions) that participate in extensive reaction networks and material processes.