We report the 364-nm negative ion photoelectron spectra of CHX(2)(-) and CDX(2)(-), where X = Cl, Br, and I. The pyramidal dihalomethyl anions undergo a large geometry change upon electron photodetachment to become nearly planar, resulting in multiple extended vibrational progressions in the photoelectron spectra. The normal mode analysis that successfully models photoelectron spectra when geom...

Using full-dimensional EOM-IP-CCSD/aug-cc-pVTZ potential energy surfaces, the photoelectron spectrum, vibrational structure, and ionization dynamics of the water dimer radical cation, (H(2)O)(2) (+), were computed. We also report an experimental photoelectron spectrum which is derived from photoionization efficiency measurements and compares favorably with the theoretical spectrum. The vibratio...

A double Rydberg anion has two electrons in diffuse orbitals that are bound by a closed-shell, cationic core. Low-energy features in the recently reported photoelectron spectrum of N2H7 2 are assigned to double Rydberg anions on the basis of electron propagator calculations employing Brueckner doubles, coupled-cluster reference states. The lowest electron detachment energy, 0.415 eV, correspond...

Electronic excited and ionized states of pyridine were reinvestigated by the symmetry-adapted cluster configuration interaction ~SAC-CI! method using an extended basis set and a wide active space. The present SAC-CI results for the singlet and triplet excited states are greatly improved and agree well with the experimental observations, providing a firm assignment of all low-lying n→p* and p→p*...

The dynamics of pyrrole excited at wavelengths in the range 242-217 nm are studied using a combination of time-resolved photoelectron spectroscopy and wavepacket propagations performed using the multi-configurational time-dependent Hartree method. Excitation close to the origin of pyrrole's electronic spectrum, at 242 and 236 nm, is found to result in an ultrafast decay of the system from the i...

Electronic structure of the oxyallyl diradical and the anion is investigated using high-level ab initio methods. Converged theoretical estimates of the energy differences between low-lying electronic states of oxyallyl (OXA) as well as detachment energies of the anion are reported. Our best estimates of the adiabatic energy differences between the anion (2)A(2) and the neutral (3)B(2) and (3)B(...

2001 This thesis entitled: Time resolved photoelectron spectroscopy with ultrafast soft x-ray light written by Lora Nugent-Glandorf has been approved for the Department of Chemistry and Biochemistry Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentione...

A K−2V photoelectron spectrum of the CO molecule, showing several core-ionized core-excited states, has been recorded and different spectral features have interpreted in terms their direct or conjugate nature.

The high-resolution photoelectron spectrum of KrO(-) was obtained using slow electron velocity-map imaging (SEVI). The SEVI spectrum reveals numerous vibronic transitions between multiple electronic states of KrO(-) and KrO, both of which are open-shell species. Detailed assignments are made by comparison with theoretical simulations based on high level ab initio calculations and an atoms-in-mo...