Vibrational predissociation spectroscopy of the H2-tagged mono- and dicarboxylate anions of dodecanedioic acid

Vibrational predissociation spectroscopy of the HOOC(CH2)10COO− and −OOC(CH2)10COO− anions is carried out by predissociation of weakly bound H2 molecules. The HOOC(CH2)10COO− (H2)2 and −OOC(CH2)10COO− (H2)10 cluster ions are formed by H2 attachment to the electrospray-generated bare ions in an ion trap cooled to below 20 K using a closed cycle helium cryostat. The photofragmentation behavior indicates that the H2 binding energy is about 600 cm−1, which is similar in strength to that found in Ar-tagged ions. The spectra indicate that the monoanion adopts a cyclic structure through the formation of an asymmetrical, internal anionic H-bond.

Graphical abstract.Figure optionsDownload full-size imageDownload high-quality image (119 K)Download as PowerPoint slideResearch highlights▶ H2 tagging of electrosprayed ions in cryogenically cooled RF ion trap. ▶ Singly and doubly charged ions analyzed by vibrational predissociation spectroscopy. ▶ Characterization of intramolecular hydrogen bonding in cyclic monoanion.