title: Conformational steering in dicarboxy acids: the native structure of succinic acid.
abstract: Succinic acid, a dicarboxylic acid molecule, has been investigated spectroscopically with computational support to elucidate the complex aspects of its conformational composition. Due to the torsional freedom of the carbon backbone and hydroxy groups, a large number of potentially plausible conformers can be generated with an indication that the gauche conformer is favored over the trans form. The microwave and millimeter wave spectra have been analyzed and accurate spectroscopic constants have been derived that correlate best with those of the lowest energy gauche conformer. For an unambiguous conformational identification measurements were extended to the monosubstituted isotopologues, precisely determining the structural properties. Besides bond distances and angles, particularly the dihedral angle has been determined to be 67.76(11)°, confirming the anomalous tendency of the methylene units to favor gauche conformers when a short aliphatic segment is placed between two carbonyl groups.
authors.affiliation: Institut für Physikalische Chemie & Elektrochemie, Lehrgebiet A, Gottfried-Wilhelm-Leibniz-Universität, Callinstraße 3a, D-30167 Hannover, Germany. michaela.jahn@pci.uni-hannover.de.
authors.forename: Michaela K
authors.initials: MK
authors.lastname: Jahn
authors.forename: Estibaliz
authors.initials: E
authors.lastname: Méndez
authors.forename: K P
authors.initials: KP
authors.lastname: Rajappan Nair
authors.forename: Peter D
authors.initials: PD
authors.lastname: Godfrey
authors.forename: Don
authors.initials: D
authors.lastname: McNaughton
authors.forename: Patricia
authors.initials: P
authors.lastname: Écija
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Basterretxea
authors.forename: Emilio J
authors.initials: EJ
authors.lastname: Cocinero
authors.forename: Jens-Uwe
authors.initials: JU
authors.lastname: Grabow
mesh_terms: D003998:Dicarboxylic Acids / Q000737:chemistry*; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D010103:Oxygen Isotopes / Q000737:chemistry; D011789:Quantum Theory; D019802:Succinic Acid / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D003998:Dicarboxylic Acids; D010103:Oxygen Isotopes; D019802:Succinic Acid