We report high-resolution anion photoelectron spectra of vanadium dioxide (VO2 (-)) obtained by slow electron velocity-map imaging of trapped and cryogenically cooled anions. Vibrationally resolved spectra are obtained for photodetachment to the first three neutral electronic states, giving an electron affinity of 1.8357(5) eV for the X̃A12 ground state and term energies of 0.1845(8) eV and 0.8130(5) eV for the ÃB12 and B̃A12 excited states, respectively. The vibrational fundamentals ν1 and ν2 are obtained for all three states. Experimental assignments are confirmed by energies from electronic structure calculations and Franck-Condon spectral simulations. These simulations support assigning the anion ground state as the X̃B13 state. With this assignment, photodetachment to the B̃A12 state involves a nominally forbidden two-electron transition, suggesting extensive configuration interaction in neutral VO2.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.4861667 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Anion photoelectron velocity-map imaging using a tunable laser at a 100 kHz repetition rate.
J Chem Phys
January 2025
Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
We present velocity-map imaging (VMI) of photoelectrons detached from anions using an optical parametric amplifier operating at a repetition rate as high as 100 kHz. The light source generates femtosecond (fs) laser pulses tunable from near-infrared to ultraviolet (310-2600 nm), which interact synchronously with mass-selected anion bunches. We demonstrate this technique by measuring two-dimensional projections of photoelectrons ejected from silver trimer anions, Ag3-, across a photon energy range from 2.
View Article and Find Full Text PDFDesign of a compact, high-resolution velocity-map imaging spectrometer for attosecond spectroscopy.
Rev Sci Instrum
January 2025
Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405 Orsay, France.
We present the design of a VMI spectrometer optimized for attosecond spectroscopy in the 0-40 eV energy range. It is based on a compact three-electrode configuration where the lens shape, size, and material have been optimized using numerical simulations to improve the spectral resolution by a factor of ∼5 relative to the initial design [Eppink and Parker, Rev. Sci.
View Article and Find Full Text PDFState-to-state scattering of highly vibrationally excited NO with argon at collision energies over 1 eV.
Phys Chem Chem Phys
January 2025
Department of Chemistry, University of Missouri, Columbia, MO 65211, USA.
We present state-to-state differential cross sections for rotationally inelastic collisions of vibrationally excited NO XΠ ( = 9) with Ar using a near-counterpropagating molecular beam geometry. These were obtained using the stimulated emission pumping technique coupled with velocity map imaging. Collision energies well over ∼1 eV were achieved and rotational excitations up to ∼Δ = 60 recorded for the first time for inelastic collisions.
View Article and Find Full Text PDFSpectroscopy and Dynamics of the Dipole-Bound States of -, -, and -Methylphenolate Anions.
J Phys Chem A
January 2025
Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.
A photodetachment and photoelectron spectroscopic study by employing a cryogenically cooled ion trap combined with a velocity-map imaging setup has been carried out to unravel the vibrational structures and autodetachment dynamics of the dipole-bound states (DBSs) of -, -, and -methylphenolate anions (-, -, and -CHPhO). The electron binding energy of the DBS increases monotonically with the increase of the neutral dipole moment to give respective values of 66 ± 15, 123 ± 18, or 154 ± 14 cm for the -, -, or -isomer. The different electron-donating effects of the methyl moieties in the three geometrically different isomers seem to be reflected in the experiment.
View Article and Find Full Text PDFDeep denoising approach to improve shear wave phase velocity map reconstruction in ultrasound elastography.
Med Phys
December 2024
Department of Electronics and Electrical Engineering, Indian Institute of Technology Guwahati, Assam, India.
Background: Measurement noise often leads to inaccurate shear wave phase velocity estimation in ultrasound shear wave elastography. Filtering techniques are commonly used for denoising the shear wavefields. However, these filters are often not sufficient, especially in fatty tissues where the signal-to-noise ratio (SNR) can be very low.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!