The photodissociation spectrum of jet-cooled PtOþ is reported over the range of 25 000 to 30 000 cm . Excited state vibrational progressions are identified for P 1=2 R3=2 and P5=2 R3=2 transitions with several vibrational peaks rotationally resolved. Additional peaks not assigned to a vibrational series also exhibit rotational structure. Transitions arising from the R3=2 ground state show a spe...

A pair of coherent femtosecond pulse excitations applied to a molecule with strong electron-phonon coupling creates a coherent superposition of a low momentum and a high momentum wavepacket in the vibrational states of both the excited state and the ground state of the coherent transition. As the excited state is accelerated further, interference between the high momentum ground state contribut...

Photodetachment cross sections are measured across the detachment threshold of Au2(-) between 1.90 and 2.02 eV using a tunable laser. In addition to obtaining a more accurate electron affinity for Au2 (1.9393 ± 0.0003 eV), we observe eight resonances above the detachment threshold, corresponding to excitations from the vibrational levels of the Au2(-) ground state (X(2)Σu(+)) to those of a meta...

The third-order polarization for coherent anti-Stokes Raman scattering (CARS) from a pure state is described by 48 terms in perturbation theory, but only 4 terms satisfy the rotating wave approximation. They are represented by Feynman dual time-line diagrams and four-wave mixing energy level diagrams. In time-resolved (tr) fs and fs/ps CARS from the ground vibrational state, one resonant diagra...

Resonantly-enhanced one-color two-photon ~111! ionization spectra of jet-cooled methylamines (CH3NH2 and CH3ND2) reveal the vibrational structures of these molecules in predissociative à states. Rotational fine structure is clearly resolved for CH3ND2 at the origin and first wagging vibrational level in the excited state. The spectral linewidth becomes homogeneously broadened to give only vibra...

Vibrational energy transfer from the first excited state 2252 cm−1 of the C–D stretch of deuterated chloroform DCCl3 to the 0-1 transition 2155 cm−1 of the CN stretch of phenyl selenocyanate C6H5SeCN in their 1:1 liquid mixture was observed with a pump/probe two-color two dimensional infrared spectroscopic technique. The mode-specific energy transfer can occur mainly because of the long vibrati...

This work presents a nonadiabatic molecular dynamics study of the nonradiative decay of photoexcited trans-azomethane, using the ab initio multiple spawning (AIMS) program that has been interfaced with the General Atomic and Molecular Electronic Structure System (GAMESS) quantum chemistry package for on-the-fly electronic structure evaluation. The interface strategy is discussed, and the capabi...

Cyclic nitramine hexahydro-1,3,5-trinitro-s-triazine (RDX), is an important energetic ingredient for propellants and explosives. To understand RDX explosive nature, the molecular structure needs to be examined in detail. Solid state RDX exist as three polymorphs: α, β and γ. The α-form is the stable polymorph at room temperature with Cs symmetry, β-polymorph has a molecular symmetry of C3v and ...

A pair of coherent femtosecond pulse excitations applied to a molecule with strong electron-phonon coupling creates a coherent superposition of a low momentum and a high momentum wavepacket in the vibrational states of both the excited state and the ground state of the coherent transition. As the excited state is accelerated further, interference between the high momentum ground state contribut...

Electronic and vibrational structures in the S(0) (1)A(1) and S(1) (1)A(1) states of jet-cooled phenanthrene-h(10) and phenanthrene-d(10) were analyzed by high-resolution spectroscopy using a tunable nanosecond pulsed laser. The normal vibrational energies and molecular structures were estimated by ab initio calculations with geometry optimization in order to carry out a normal-mode analysis of...