Structural transitions in benzene–argon clusters: Size and temperature effects

Schmidt, Martin; Le Calvé, Jacques; Mons, Michel
April 1993
Journal of Chemical Physics;4/15/1993, Vol. 98 Issue 8, p6102
Academic Journal
The resonant two-photon ionization spectra of the first benzene–Arn (n≤8) clusters are interpreted in the light of a model calculation, including local energy minima determinations and Monte Carlo simulations. Based on spectral shift information, two types of structures are distinguished: the argon cluster either only solvates one side of the substrate molecule or covers simultaneously both sides. The ‘‘wettest’’ structures are assigned to sandwich-type forms for n≤4 and to clamshell-type forms beyond. Such a 2D–3D transition in the n=5–8 size range is shown to be specific to small substrate size. In the one-sided forms, the argon cluster geometry is strongly influenced by the presence of the Bz molecule since it adopts a quasiplanar geometry, more or less tightly bound to the substrate depending on its size: the small argon clusters exhibit two types of complexation sites (c and s forms) which are simultaneously visited (surface decoupling) even at low temperature (∼7 K). As the size increases, the c form becomes prevalent and the surface decoupling becomes inhibited. At n=8 a 2D–3D transition is observed: beyond the n=7 species, characterized by a caplike close-packed structure, the one-sided conformers disappear in favor of bridged forms. Additional results on the ionization behavior of the one-sided species show regular variation of the ionization potential with the cluster size.


Related Articles

  • Stretch–bend coupling between van der Waals modes in the S1 state of substituted benzene–Ar1 complexes. Bieske, Evan J.; Rainbird, Mark W.; Atkinson, Ian M.; Knight, Alan E. W. // Journal of Chemical Physics;7/15/1989, Vol. 91 Issue 2, p752 

    The van der Waals vibrations of aniline–, phenol–, fluorobenzene–, and chlorobenzene–Ar1 complexes have been measured using one-color resonance enhanced multiphoton ionization spectroscopy, together with time-of-flight mass spectrometry, in a skimmed supersonic...

  • One- and two-color multiphoton ionization of argon. Li, Leping; Wu, Ming; Johnson, Philip M. // Journal of Chemical Physics;9/15/1988, Vol. 89 Issue 6, p3470 

    A systematic explanation of the pressure-dependent multiphoton ionization spectra of argon is given in terms of the phase matching requirements of third-harmonic generation. Two-color sum-frequency generation in a highly dispersive medium and its effects on normal three-photon excitation process...

  • Origin of the line shapes from intramolecular Penning ionization in benzene/argon clusters. Kamke, B.; Kamke, W.; Wang, Z.; Rühl, E.; Brutschy, B. // Journal of Chemical Physics;3/1/1987, Vol. 86 Issue 5, p2525 

    A supersonic beam of benzene (Bz) seeded in argon was ionized by VUV radiation from the Berlin electron storage ring (BESSY). Resonance structures in the photoionization efficiency curves of Bz and Bz·Arn (n=1,...,4) are attributed to intramolecular Penning ionization after excitation of...

  • Two-photon ionization studies of binary aromatic van der Waals clusters: Benzene...chlorobenzene and (chlorobenzene)2. Lu, Wenyun; Hu, Yihua; Lin, Zhenyang; Yang, Shihe // Journal of Chemical Physics;6/8/1996, Vol. 104 Issue 22, p8843 

    Jet-cooled van der Waals dimers of benzene (B) and chlorobenzene (BCl) were studied by one-color resonant two-photon ionization through the S0→S1 transition of the chlorobenzene. The spectra of BCl...B and (BCl)2 in the 0–0 band both show two main features with different spectral...

  • Fast decay of high vibronic S[sub 1] states in gas-phase benzene. Clara, M.; Hellerer, Th.; Neusser, H.J. // Applied Physics B: Lasers & Optics;2000, Vol. 71 Issue 3, p431 

    Abstract. Lifetimes of different vibronic levels at high excess energies in the S[sub 1 state of isolated benzene molecules are measured using for the first time a two-photon ionization pump-probe technique with UV femtosecond pulses. For the 6[sup 1] 1[sup 3] state (3290 cm[sup -1] excess...

  • A spectroscopic investigation of the nonrigid–rigid transition of (benzene)13 during free jet expansion. Easter, David C.; Baronavski, A. P.; Hawley, Michael // Journal of Chemical Physics;10/1/1993, Vol. 99 Issue 7, p4942 

    We have traced the evolution of the benzene-h6 transition in (C6H6)(C6D6)12 as a function of time (distance from the nozzle) in a supersonic expansion. Taking advantage of the special properties of the isotopically substituted (benzene)13 resonant two-photon ionization spectrum, we present the...

  • Direct measurements of vibrational predissociation of p-difluorobenzene–argon. Jacobson, Benjamin A.; Humphrey, Stephen; Rice, Stuart A. // Journal of Chemical Physics;11/1/1988, Vol. 89 Issue 9, p5624 

    We have measured rates of vibrational predissociation from 12 vibrational levels of S1 p-difluorobenzene–argon (pDFB–Ar) by time-resolved two-color multiphoton ionization. Three features of our results are particularly surprising. First, the vibrational predissociation rate does...

  • Optimization of few-cycle laser pulse pumped high-order harmonic generation at 60-70 eV by changing the gas pressure. Wang, Li-Feng; He, Xin-Kui; Teng, Hao; Yun, Chen-Xia; Zhang, Wei; Wei, Zhiyi // Applied Physics B: Lasers & Optics;Oct2015, Vol. 121 Issue 1, p81 

    We have experimentally investigated the gas cell pressure effect of high-order harmonic generation in argon and neon. The selective enhancement of high-order harmonic intensity in the energy range of 60-70 eV in the spectrum has been obtained in argon. The experimental results are simulated...

  • Resonant two-photon ionization and ab initio conformational analysis of haloethyl benzenes (PhCH2CH2X,X=Cl,F). Martin, Danielle E.; Robertson, Evan G.; Morrison, Richard J. S.; Dobney, Bruce // Journal of Chemical Physics;10/7/2007, Vol. 127 Issue 13, p134307 

    The S1←S0 transitions of the gaseous (2-fluoroethyl)-benzene (FEB) and (2-chloroethyl)-benzene (CEB) have been investigated using a combination of two-color resonant two-photon ionization and UV-UV hole burning spectroscopy. Both anti and gauche conformers have been identified on the basis...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics