Geminal

Molecular-structure relationship

In chemistry, the descriptor geminal (from Latin gemini 'twins') refers to the relationship between two atoms or functional groups that are attached to the same atom. A geminal diol, for example, is a diol (a molecule that has two alcohol functional groups) attached to the same carbon atom, as in methanediol. Also the shortened prefix gem may be applied to a chemical name to denote this relationship, as in a gem-dibromide for "geminal dibromide".

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