The size dependence of ground-state collective vibrational modes in molecular clusters. Benzene dimer through pentamer

Schaeffer, Mark W.; Maxton, Patrick M.; Felker, Peter

doi:10.1016/0009-2614(94)00575-3

Cited by 30 publications

(13 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…reported that Bz 2 has lower frequency intermolecular vibrations than those of Bz 3 . 68 On the other hand, W(E v − E diss ) of the (Bz 2 + Bz) fragments of Bz 3 will be larger than that of the (Bz + Bz) fragments of Bz 2 , when one assumes that the dissociation energy is not so different between Bz 2 and Bz 3 . The lower ρ(E v ) and larger W(E v − E diss ) of Bz 3 will result in faster VP rate constant of Bz 3 than that of Bz 2 .…”

Section: F Ver Of Bzmentioning

confidence: 99%

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Kusaka

Inokuchi

Ebata

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

Vibrational energy relaxation (VER) of the Fermi polyads in the CH stretching vibration of the benzene dimer (Bz(2)) and trimer (Bz(3)) has been investigated by picosecond (ps) time-resolved IR-UV pump-probe spectroscopy in a supersonic beam. The vibrational bands in the 3000-3100 cm(-1) region were excited by a ps IR pulse and the time evolutions at the pumped and redistributed (bath) levels were probed by resonance enhanced multiphoton ionization with a ps UV pulse. For Bz(2), a site-selective excitation in the T-shaped structure was achieved by using the isotope-substituted heterodimer hd, where h = C(6)H(6) and d = C(6)D(6), and its result was compared with that of hh homodimer. In the hd heterodimer, the two isomers, h(stem)d(top) and h(top)d(stem), show remarkable site-dependence of the lifetime of intracluster vibrational energy redistribution (IVR); the lifetime of the Stem site [h(stem)d(top), 140-170 ps] is ~2.5 times shorter than that of the Top site [h(top)d(stem), 370-400 ps]. In the transient UV spectra, a broad electronic transition due to the bath modes emerges and gradually decays with a nanosecond time scale. The broad transition shows different time profile depending on UV frequency monitored. These time profiles are described by a three-step VER model involving IVR and vibrational predissociation: initial → bath1(intramolecular) → bath2(intermolecular) → fragments. This model also describes well the observed time profile of the Bz fragment. The hh homodimer shows the stepwise VER process with time constants similar to those of the hd dimer, suggesting that the excitation-exchange coupling of the vibrations between the two sites is very weak. Bz(3) also exhibited the stepwise VER process, though each step is faster than Bz(2).

show abstract

Section: F Ver Of Bzmentioning

confidence: 99%

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Kusaka

Inokuchi

Ebata

2012

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…The quadrupole moment 83,84 of CS 2 may give rise to aggregate-like structures in the liquid, resembling small clusters . Like in gas-phase clusters, collective low-frequency vibrations are then expected to contribute significantly to the observed Rayleigh-wing spectra. , …”

Section: Alternative Scattering Mechanismsmentioning

confidence: 99%

“…74 Like in gas-phase clusters, collective low-frequency vibrations are then expected to contribute significantly to the observed Rayleigh-wing spectra. 74,85 In the DLS theory, the collective local modes are described by the dynamic pair correlation function C p (t), defined in eq 10. At t ) 0 this quantity is closely related to the static orientational correlation parameter g 2 which is a measure for the average local ordering in the liquid.…”

Section: Alternative Scattering Mechanismsmentioning

confidence: 99%

Microscopic Origin of the Optical Kerr Effect Response of CS₂−Pentane Binary Mixtures

1998

View full text Add to dashboard Cite

The femtosecond optically heterodyned detected optical Kerr effect (OHD-OKE) response of carbon disulfide/pentane binary mixtures is reported for various concentrations. As pentane is added, three trends are observed: the instantaneous electronic contribution gets more pronounced, the picosecond diffusive reorientation becomes faster, and the subpicosecond inertia-limited response slows down. The corresponding frequency domain representation of the latter component narrows and shifts toward lower frequencies. These spectral changes occur exclusively when the CS2 concentration is lowered from 100 to 20 vol %; at still lower concentrations no further changes are observed. When the nondiffusive part of the optical response is assigned exclusively to coherent intermolecular vibrations, the spectral changes can be attributed to a reduced inhomogeneous broadening, reflecting a narrowing of the distribution of oscillator frequencies. However, we argue here that because of the observed concentration dependence the validity of this model is questionable. Long-range interaction-induced effects and short-range collision-induced processes are additional scattering mechanisms that may contribute substantially to the observed spectra.

show abstract

“…The structure of Bz 2 in the electronic ground state has been thoroughly investigated for a long time due to the fundamental importance as the simplest model of aromatic-aromatic interactions. Experimentally, only the T-shaped dimer has been observed in the gas phase, [38][39][40][41][42][43][44] while both the T and SW structures have been proposed by quantum chemical calculations with nearly identical stabilization energies. [30][31][32][33][34] The clusters of Bz in the gas phase were reported by Shinohara and Nishi via the S 2 excited state, and the EXC formation was suggested.…”

Section: Introductionmentioning

confidence: 99%

Real time observation of the excimer formation dynamics of a gas phase benzene dimer by picosecond pump–probe spectroscopy

Miyazaki

Fujii

2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

We observed the real-time excimer (EXC) formation dynamics of a gas phase benzene dimer (Bz2) cluster after photo-excitation to the S1 state by applying an ionization detected picosecond transient absorption method for probing the visible EXC absorption for the first time. The time evolution of the EXC absorption from the S1 0(0) level shows a rise that is well fitted by a single exponential function with a time constant of 18 ± 2 ps. The structure of the Bz dimer has a T-shaped structure in the ground electronic state, and that in the EXC state is a parallel sandwich (SW) structure. Thus, the observed rise time corresponds to the structural change from the T to the SW structures, which directly shows the EXC formation. On the other hand, the EXC formation after excitation of the S1 6(1) vibrational level of the stem site showed a faster rise of the time constant of 10 ± 2 ps. Supposing equilibrium between the EXC and the local excited states, it followed that the intramolecular vibrational energy redistribution rate of the 6(1) level is largely enhanced and becomes faster than the EXC formation reaction.

show abstract

The size dependence of ground-state collective vibrational modes in molecular clusters. Benzene dimer through pentamer

Cited by 30 publications

References 31 publications

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Microscopic Origin of the Optical Kerr Effect Response of CS₂−Pentane Binary Mixtures

Real time observation of the excimer formation dynamics of a gas phase benzene dimer by picosecond pump–probe spectroscopy

Contact Info

Product

Resources

About

The size dependence of ground-state collective vibrational modes in molecular clusters. Benzene dimer through pentamer

Cited by 30 publications

References 31 publications

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Vibrational energy relaxation of benzene dimer and trimer in the CH stretching region studied by picosecond time-resolved IR-UV pump-probe spectroscopy

Microscopic Origin of the Optical Kerr Effect Response of CS2−Pentane Binary Mixtures

Real time observation of the excimer formation dynamics of a gas phase benzene dimer by picosecond pump–probe spectroscopy

Contact Info

Product

Resources

About

Microscopic Origin of the Optical Kerr Effect Response of CS₂−Pentane Binary Mixtures