What is another name for cis-trans isomers?

Cis-trans isomers are commonly referred to as geometric isomers. This terminology arises from the specific arrangement of substituents around a double bond or a ring structure, which leads to distinct spatial configurations. In cis isomers, similar groups are on the same side of the double bond or ring, while in trans isomers, they are on opposite sides. This distinction affects the physical and chemical properties of the compounds, impacting aspects like boiling points, solubility, and reactivity.

The term "geometric isomers" effectively encompasses these variations in spatial arrangement, highlighting the importance of orientation in determining their chemical behavior. In contrast, structural isomers refer to compounds that have the same molecular formula but different connectivity of atoms, while functional isomers involve different functional groups that can be created from the same molecular formula. Optical isomers are another class entirely, related to chirality and the ability of molecules to rotate polarized light, which does not apply to cis-trans isomers. Thus, the name "geometric isomers" is the most accurate alternative to cis-trans isomers.