The mass spectra of carboxylic acids·IV: Carboxyl‐carboxyl interaction in some cycloalkane 1,2 dicarboxylic acids and its relationship with molecular geometry

The interaction of the carboxyl groups in the fragmentation of the molecular ions of trans cyclohexane‐1,2‐dicarboxylic acid and cis cyclobutane‐1,2‐dicarboxylic acid serves to distinguish these acids from their cis and trans isomers respectively. This ‘ortho effect’ can be related to the geometrical arrangement of the carboxyl groups in the ground‐state molecules.