TY - JOUR

T1 - Hydrogen Bonding to Alkanes: Computational Evidence

AU - Hammerum, Steen

AU - Olesen, Solveig Gaarn

PY - 2009

Y1 - 2009

N2 - The structural, vibrational, and energetic properties of adducts ofalkanes and strong cationic proton donors were studied with composite abinitio calculations. Hydrogen bonding in [D-H+ H-alkyl] adductscontributes to a significant degree to the interactions between the twocomponents, which is substantiated by NBO and AIM results. The hydrogenbonds manifest themselves in the same manner as conventional hydrogenbonds, D-H bond elongation, D-H vibrational stretching frequency red shiftand intensity increase, and adduct stabilization. The alkane adductsalso exhibit elongation of the C-H bonds involved and a concurrent redshift, which is rationalized in terms of charge-transfer interactionsthat cause simultaneous weakening of both the O-H and C-H bonds. Likeother dihydrogen-bonded adducts, the adducts possess a bent structureand asymmetric bifurcated hydrogen bonds. The hydrogen bonds are strongerin adducts of isobutane and in adducts of stronger acids. Intramolecularhydrogen bonding in protonated long-chain alcohols manifests itself in thesame manner as intermolecular hydrogen bonding and can be equally strong. Udgivelsesdato: 12 juni 2009

AB - The structural, vibrational, and energetic properties of adducts ofalkanes and strong cationic proton donors were studied with composite abinitio calculations. Hydrogen bonding in [D-H+ H-alkyl] adductscontributes to a significant degree to the interactions between the twocomponents, which is substantiated by NBO and AIM results. The hydrogenbonds manifest themselves in the same manner as conventional hydrogenbonds, D-H bond elongation, D-H vibrational stretching frequency red shiftand intensity increase, and adduct stabilization. The alkane adductsalso exhibit elongation of the C-H bonds involved and a concurrent redshift, which is rationalized in terms of charge-transfer interactionsthat cause simultaneous weakening of both the O-H and C-H bonds. Likeother dihydrogen-bonded adducts, the adducts possess a bent structureand asymmetric bifurcated hydrogen bonds. The hydrogen bonds are strongerin adducts of isobutane and in adducts of stronger acids. Intramolecularhydrogen bonding in protonated long-chain alcohols manifests itself in thesame manner as intermolecular hydrogen bonding and can be equally strong. Udgivelsesdato: 12 juni 2009

KW - Faculty of Science

U2 - 10.1021/jp9030392

DO - 10.1021/jp9030392

M3 - Journal article

C2 - 19522536

VL - 113

SP - 7940

EP - 7944

JO - Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory

JF - Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory

SN - 1089-5639

ER -