Direct infrared absorption spectroscopy of benzene dimer.

The direct infrared (IR) absorption spectrum of benzene dimer formed in a free-jet expansion was recorded in the 3.3 μm region for the first time. This has led to the observation of the C-H stretching fundamental mode ν(13) (B(1u)), which is both IR and Raman forbidden in the monomer. Moreover, the IR forbidden and Raman allowed ν(7) (E(2g)) mode has been observed as well. These two modes were found to be red-shifted along with the IR allowed ν(20) (E(1u)) mode, as previously reported by Erlekam et al. [Erlekam; Frankowski; Meijer; Gert von Helden J. Chem. Phys.2006, 124, 171101], using ion-dip spectroscopy, contrary to the blue-shift predicted earlier by theoretical studies. The observation of the ν(13) band indicates that the symmetry is reduced in the dimer, confirming the T-shaped structure observed by Erlekam et al. Our experimental results have not provided any direct evidence for the presence of the parallel displaced geometry, the main objective of the present work, as predicted by theoretical calculations.

[1]  R. Georges,et al.  Direct absorption spectroscopy of water clusters formed in a continuous slit nozzle expansion. , 2009, The Journal of chemical physics.

[2]  G. Seifert,et al.  Correction for dispersion and Coulombic interactions in molecular clusters with density functional derived methods: application to polycyclic aromatic hydrocarbon clusters. , 2009, The Journal of chemical physics.

[3]  P. Hobza,et al.  Benzene Dimer: Dynamic Structure and Thermodynamics Derived from On-the-Fly ab initio DFT-D Molecular Dynamic Simulations. , 2008, Journal of chemical theory and computation.

[4]  E. Schröder,et al.  Stacking interactions and the twist of DNA. , 2008, Journal of the American Chemical Society.

[5]  P. Hobza,et al.  C-H stretching vibrational shift of benzene dimer: consistency of experiment and calculation. , 2007, Chemphyschem : a European journal of chemical physics and physical chemistry.

[6]  S. Wetmore,et al.  Characterization of the stacking interactions between DNA or RNA nucleobases and the aromatic amino acids , 2007 .

[7]  S. Grimme,et al.  Double-hybrid density functionals with long-range dispersion corrections: higher accuracy and extended applicability. , 2007, Physical chemistry chemical physics : PCCP.

[8]  A. Goursot,et al.  Interaction between n-Alkane Chains:  Applicability of the Empirically Corrected Density Functional Theory for Van der Waals Complexes. , 2007, Journal of chemical theory and computation.

[9]  Krzysztof Szalewicz,et al.  Potential energy surface for the benzene dimer and perturbational analysis of π-π interactions , 2006 .

[10]  M. Frankowski,et al.  An experimental value for the B(1u) C-H stretch mode in benzene. , 2006, The Journal of chemical physics.

[11]  P. Hobza,et al.  Theoretical investigations into the blue-shifting hydrogen bond in benzene complexes. , 2006, Chemphyschem : a European journal of chemical physics and physical chemistry.

[12]  Marcey L Waters,et al.  Aromatic interactions in model systems. , 2002, Current opinion in chemical biology.

[13]  F. Gervasio,et al.  Stacking and T-shape competition in aromatic-aromatic amino acid interactions. , 2002, Journal of the American Chemical Society.

[14]  S. Tsuzuki,et al.  Origin of attraction and directionality of the pi/pi interaction: model chemistry calculations of benzene dimer interaction. , 2002, Journal of the American Chemical Society.

[15]  Pavel Hobza,et al.  Blue-Shifting Hydrogen Bonds. , 2000, Chemical reviews.

[16]  G. McGaughey,et al.  pi-Stacking interactions. Alive and well in proteins. , 1998, The Journal of biological chemistry.

[17]  Pavel Hobza,et al.  Anti-Hydrogen Bond in the Benzene Dimer and Other Carbon Proton Donor Complexes , 1998 .

[18]  C. Hunter.  Meldola Lecture. The role of aromatic interactions in molecular recognition , 1994 .

[19]  V. A. Venturo,et al.  Intermolecular Raman bands in the ground state of benzene dimer , 1993 .

[20]  Elangannan Arunan,et al.  The rotational spectrum, structure and dynamics of a benzene dimer , 1993 .

[21]  P. Felker,et al.  RAMAN-VIBRONIC DOUBLE RESONANCE SPECTROSCOPY OF BENZENE DIMER , 1992 .

[22]  M. Junttila,et al.  Molecular-beam spectrum of the 3.3-μm ν12 band of benzene , 1991 .

[23]  L Serrano,et al.  Aromatic-aromatic interactions and protein stability. Investigation by double-mutant cycles. , 1991, Journal of molecular biology.

[24]  Y. Shen,et al.  Local modes of benzene and benzene dimer, studied by infrared–ultraviolet double resonance in a supersonic beam , 1988 .

[25]  E. W. Schlag,et al.  Spectra of isotopically mixed benzene dimers: Details on the interaction in the vdW bond , 1986 .

[26]  Mark Schauer,et al.  Dimers of aromatic molecules: (Benzene)2, (toluene)2, and benzene–toluene , 1984 .

[27]  S. Colson,et al.  FTIR spectrum of benzene in a supersonic expansion , 1984 .

[28]  Stephen J. Harris,et al.  Benzene dimer: A polar molecule , 1975 .