geometric isomers

[qazwsxedc]

Are geometric isomers optically active? They don't have a chiral center, and I thought you needed a chiral center to be optically active? It seems though that the only diastereomer that is optically inactive is the meso compound. Could somoene please clarify? Thanks in advance

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[BerkReviewTeach]

Are geometric isomers optically active? They don't have a chiral center, and I thought you needed a chiral center to be optically active? It seems though that the only diastereomer that is optically inactive is the meso compound. Could somoene please clarify? Thanks in advance

Geometrical isomers in terms of pi-bonds? Those are not optically active unless there is a stereogenic center somewhere else on the molecule.

If you are thinking of cis-trans isomers associated with cyclopentane or cyclohexane, then they can are generally optically active unless the compound happens to be meso.

A cool brain teaser of a problem involves cis-1,4-dimethylcyclohexane versus trans-1,4-dimethylcyclohexane. Neither rotate plane polarized light and they are diastereomers.