6 Zero electron kinetic energy photoelectron spectra of metal clusters and complexes

1994 ◽

Vol 72 (11-12) ◽

pp. 1322-1335 ◽

Cited By ~ 30

Author(s):

Caroline C. Arnold ◽

Daniel M. Neumark

Keyword(s):

Excited State ◽

Kinetic Energy ◽

Ground State ◽

Photoelectron Spectra ◽

Negative Ion ◽

Electron Affinities ◽

Electron Kinetic Energy ◽

First Excited State ◽

State Frequency ◽

Term Energy

The zero electron kinetic energy (ZEKE) spectra of In2P− and InP2− are presented and compared to their previously obtained photoelectron spectra (PES) as well as ab initio calculations on analogous species. The threshold spectra, which give high-accuracy electron affinities of 2.400 ± 0.001 eV for In2P and 1.617 ± 0.001 eV for InP2, show well-resolved vibrational structure in the transitions from the ground anion states to the various neutral states. The ZEKE spectrum of In2P− exhibits a fairly extended, 47 cm−1 progression that we assign to the symmetric bend (ν2) in the ground 2B2 neutral state. There is also a 204 cm−1 progression that we assign to the symmetric stretch. The InP2− ZEKE spectrum shows transitions to two electronic states of the neutral. For the ground state, the symmetric stretch mode is the most active in the spectrum, whereas in the excited state, the symmetric bend mode is most active. The InP2 ground-state symmetric stretch frequency is 190 cm−1, and the excited-state symmetric bend frequency is 287 cm−1. An anion ground-state frequency is determined to be 227 cm−1. The term energy of the excited state is determined to be 1.280 ± 0.001 eV. Based on molecular orbital arguments, these frequencies suggest a 2B2 ground InP2 state, a 2A1 first excited state, and a 1A1 anion ground state.

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Vibrational and geometric structures of Nb3C2 and Nb3C+2 from pulsed field ionization‐zero electron kinetic energy photoelectron spectra and density functional calculations

The Journal of Chemical Physics ◽

10.1063/1.472873 ◽

1996 ◽

Vol 105 (24) ◽

pp. 10663-10671 ◽

Cited By ~ 59

Author(s):

Dong‐Sheng Yang ◽

Marek Z. Zgierski ◽

Attila Bérces ◽

Peter A. Hackett ◽

Pierre‐Nicholas Roy ◽

...

Keyword(s):

Kinetic Energy ◽

Density Functional Calculations ◽

Density Functional ◽

Photoelectron Spectra ◽

Field Ionization ◽

Geometric Structures ◽

Pulsed Field ◽

Electron Kinetic Energy ◽

Pulsed Field Ionization

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VUV FRAGMENTATION OF SOME HYDROFLUOROCARBON CATIONS STUDIED USING COINCIDENCE TECHNIQUES

Surface Review and Letters ◽

10.1142/s0218625x0200204x ◽

2002 ◽

Vol 09 (01) ◽

pp. 153-158 ◽

Cited By ~ 5

Author(s):

WEIDONG ZHOU ◽

D. P. SECCOMBE ◽

R. Y. L. CHIM ◽

R. P. TUCKETT

Keyword(s):

Kinetic Energy ◽

Ab Initio ◽

Ground State ◽

Lower Energy ◽

Lone Pair ◽

Electronic States ◽

Photoelectron Spectra ◽

Highest Occupied Molecular Orbital ◽

Impulsive Model ◽

Lone Pair Electrons

Threshold photoelectron–photoion coincidence (TPEPICO) spectroscopy has been used to investigate the decay dynamics of the valence electronic states of the parent cation of several hydrofluorocarbons (HFC), based on fluorine-substituted ethane, in the energy range 11–25 eV. We present data for CF 3– CHF 2, CF 3– CH 2 F , CF 3– CH 3 and CHF 2– CH 3. The threshold photoelectron spectra (TPES) of these molecules show a common feature of a broad, relatively weak ground state, associated with electron removal from the highest-occupied molecular orbital (HOMO) having mainly C–C σ-bonding character. Adiabatic and vertical ionisation energies for the HOMO of the four HFCs are presented, together with corresponding values from ab initio calculations. For those lower-energy molecular orbitals associated with non-bonding fluorine 2pπ lone pair electrons, these electronic states of the HFC cation decay impulsively by C–F bond fission with considerable release of translational kinetic energy. Appearance energies are presented for formation of the daughter cation formed by such a process (e.g. CF 3– CHF +), together with ab initio energies of the corresponding dissociation channel (e.g. CF 3– CHF + + F ). Values for the translational kinetic energy released are compared with the predictions of a pure-impulsive model.

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