scholarly journals Binding energy of solvated electrons and retrieval of true UV photoelectron spectra of liquids

2019 ◽  
Vol 5 (8) ◽  
pp. eaaw6896 ◽  
Author(s):  
Junichi Nishitani ◽  
Yo-ichi Yamamoto ◽  
Christopher W. West ◽  
Shutaro Karashima ◽  
Toshinori Suzuki

The electronic energy and dynamics of solvated electrons, the simplest yet elusive chemical species, is of interest in chemistry, physics, and biology. Here, we present the electron binding energy distributions of solvated electrons in liquid water, methanol, and ethanol accurately measured using extreme ultraviolet (EUV) photoelectron spectroscopy of liquids with a single-order high harmonic. The distributions are Gaussian in all cases. Using the EUV and UV photoelectron spectra of solvated electrons, we succeeded in retrieving sharp electron kinetic energy distributions from the spectra broadened and energy shifted by inelastic scattering in liquids, overcoming an obstacle in ultrafast UV photoelectron spectroscopy of liquids. The method is demonstrated for the benchmark systems of charge transfer to solvent reaction and ultrafast internal conversion of hydrated electron from the first excited state.

2019 ◽  
Vol 205 ◽  
pp. 02014
Author(s):  
Peng Zhao ◽  
Christopher Corder ◽  
Jin Bakalis ◽  
Xinlong Li ◽  
Matthew D. Kershis ◽  
...  

We present photoelectron spectroscopy experiments using an 88 MHz cavityenhanced high-harmonic source operating from 8 to 40 eV. Nanoampere space-charge free sample photo currents enable us to record time-resolved photoelectron spectra from weakly excited samples.


1981 ◽  
Vol 36 (1) ◽  
pp. 68-71
Author(s):  
Lucilla Alagna ◽  
Carla Cauletti ◽  
Marco Andreocci ◽  
Claudio Furlani ◽  
Gerhard Hagele

Ultraviolet photoelectron spectra (UPS) of tetrasubstituted diphosphine disulfides RR'P(S)- P(S)RR' exhibit peculiar 1:2:1 splitting patterns in the region 7.5-9.5 eV for which a throughbond coupling mechanism between the sulfur lone pairs lying in the PPS planes is proposed. Further bond orbitals are related to bands at higher I. E. in the UP spectra


1995 ◽  
Vol 60 (3) ◽  
pp. 383-392 ◽  
Author(s):  
Zdeněk Bastl

The effects of ion bombardment and r.f. plasma oxidation of graphite surfaces on subsequent growth and electronic properties of vacuum deposited palladium clusters have been investigated by methods of X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy with X-ray excitation (XAES). Due to the significantly increased density of surface defects on which the nucleation process occurs the bulk value of the Pd 3d core level binding energy is achieved at higher surface coverage by palladium on bombarded surfaces than on ordered graphite. Angle resolved photoelectron spectra of oxidized graphite surfaces reveal significant embedding of oxygen in graphite surface layers. The C 1s and O 1s photoelectron spectra are consistent with presence of two major oxygen species involving C-O and C=O type linkages which are not homogeneously distributed within the graphite surface layers. Two effects were observed on oxidized surfaces: an increase of palladium dispersion and interaction of the metal clusters with surface oxygen groups. Using the simple interpretation of the modified Auger parameter the relaxation and chemical shift contributions to the measured Pd core level shifts are estimated. In the region of low surface coverage by palladium the effect of palladium-oxygen interaction on Pd core level binding energy exceeds the effects of increased dispersity.


1982 ◽  
Vol 37 (2) ◽  
pp. 179-185 ◽  
Author(s):  
Jaap N. Louwen ◽  
Jaap Hart ◽  
Derk J. Stufkens ◽  
Ad Oskam

Abstract By means of UV photoelectron spectroscopy (UPS) the electronic structures of [Feη3.C3H5(CO)3X], [Feη3-(2-CH3C3H4)(CO)3X] (X = Cl, Br, I) and [Co(C3H5)(CO)3] have been studied. Detailed assignments are possible and surprisingly low ionization energies (as low as 8.19 eV) are found for iodine lone pair type Orbitals. From the spectra a large difference in π backbonding is found between the cobalt and iron complexes


2016 ◽  
Vol 194 ◽  
pp. 147-160 ◽  
Author(s):  
Ryo Iikubo ◽  
Taro Sekikawa ◽  
Yu Harabuchi ◽  
Tetsuya Taketsugu

Femtosecond ring-opening dynamics of 1,3-cyclohexadiene (CHD) in gas phase upon two-photon excitation at 400 nm (=3.1 eV) was investigated by time-resolved photoelectron spectroscopy using 42 nm (=29.5 eV) high harmonic photons probing the dynamics of the lower-lying occupied molecular orbitals (MOs), which are the fingerprints of the molecular structure. After 500 fs, the photoelectron intensity of the MO constituting the CC sigma bond (σCC) of CHD was enhanced, while that of the MO forming the C–C sigma bond (σCC) of CHD was decreased. The changes in the photoelectron spectra suggest that the ring of CHD opens to form a 1,3,5-hexatriene (HT) after 500 fs. The dynamics of the σCC and σCC bands between 200 and 500 fs reflects the ring deformation to a conical intersection between the 21A and 11A potential energy surfaces prior to the ring-opening reaction.


2016 ◽  
Vol 2 (2) ◽  
pp. e1501333 ◽  
Author(s):  
Cong Chen ◽  
Zhensheng Tao ◽  
Carlos Hernández-García ◽  
Piotr Matyba ◽  
Adra Carr ◽  
...  

Bright, circularly polarized, extreme ultraviolet (EUV) and soft x-ray high-harmonic beams can now be produced using counter-rotating circularly polarized driving laser fields. Although the resulting circularly polarized harmonics consist of relatively simple pairs of peaks in the spectral domain, in the time domain, the field is predicted to emerge as a complex series of rotating linearly polarized bursts, varying rapidly in amplitude, frequency, and polarization. We extend attosecond metrology techniques to circularly polarized light by simultaneously irradiating a copper surface with circularly polarized high-harmonic and linearly polarized infrared laser fields. The resulting temporal modulation of the photoelectron spectra carries essential phase information about the EUV field. Utilizing the polarization selectivity of the solid surface and by rotating the circularly polarized EUV field in space, we fully retrieve the amplitude and phase of the circularly polarized harmonics, allowing us to reconstruct one of the most complex coherent light fields produced to date.


2019 ◽  
Vol 19 (03) ◽  
pp. 1950019
Author(s):  
A. R. Yadav ◽  
S. K. Dubey ◽  
R. L. Dubey ◽  
N. Subramanyam ◽  
I. Sulania

Gallium arsenide (GaAs) implanted with silicon forming intersubband of SiGaAs is a promising material for making novel electronic and optoelectronic devices. This paper is focused on finding optimum fluence condition for formation of intersubband of SiGaAs in GaAs sample after implantation with 50[Formula: see text]keV silicon negative ions with fluences varying between [Formula: see text] and [Formula: see text] ions cm[Formula: see text]. The GaAs samples were investigated using X-ray photoelectron spectroscopy (XPS), UV-Vis.-NIR spectroscopy and X-ray diffraction (XRD) techniques. The X-ray photoelectron spectra for unimplanted sample showed peaks at binding energy of 18.74[Formula: see text]eV and 40.74[Formula: see text]eV indicating Ga3d and As3d core level, whereas the corresponding core level peaks for implanted sample were observed at binding energy of 19.25[Formula: see text]eV and 41.32[Formula: see text]eV. The shift in Ga3d and As3d core levels towards higher binding energy side in the implanted sample with respect to unimplanted sample were indicative of change in chemical state environment of Ga–As bond. The relative atomic percentage concentration of elemental composition measured using casa XPS software showed change in As/Ga ratio from 0.89 for unimplanted sample to 1.13 for sample implanted with the fluence of [Formula: see text] ion cm[Formula: see text]. The UV-Vis-NIR spectra showed absorption band between 1.365[Formula: see text]eV and 1.375[Formula: see text]eV due to the formation of intersubband of SiGaAs for fluences greater than [Formula: see text] ion cm[Formula: see text]. The GaAs crystallite size calculated using Brus formula was found to vary between 162[Formula: see text]nm and 540[Formula: see text]nm, respectively. The XRD spectra showed the presence of Bragg’s peak at 53.98∘ indicating (311) silicon reflection. The silicon crystallite size determined from full width at half maxima (FWHM) of (311) XRD peak was found to vary between 110[Formula: see text]nm and 161[Formula: see text]nm, respectively.


1986 ◽  
Vol 64 (3) ◽  
pp. 528-531 ◽  
Author(s):  
A. Katrib ◽  
B.D. El-Issa ◽  
A. W. Potts

The assignment of the four outermost ionization energies obtained by uv-photoelectron spectroscopy (UPS) of p-N,N-dimethylaminobenzalmalonitrile is given. The X-ray photoelectron spectroscopy of the N ls and C ls core levels are also discussed. Two "shake-up" lines were observed at the high binding energy side of the N ls spectral line. The energies of these spectral lines were found to correlate very well with the uv–visible spectrum. Also the energy difference of the two "shake-up" lines was found to be similar to the energy difference between the first and second ionization energies obtained by ups techniques. Only one "shake-up" line was observed in the case of C ls photoionization. Theoretical studies by semiempirical methods including HAM/3, MINDO/3, and extended Hückel are also discussed.


The principal features of helium 584 A photoelectron spectra of molecular vapours are outlined. Factors affecting the number of bands observed and their relation to the number of occupied electronic energy levels are discussed. The effect of the molecular translational velocity on the fundamental line widths attainable is considered and is shown to be significant though generally small compared with the much more common line broadening arising from ionic decomposition. Sharp lines are often to be associated with the presence of classical lone pairs but exceptions are noted. Structural effects in the lone pair ionization of chloro- and bromo-compounds are indicated. Some evidence is given for a correlation between the change in vibrational frequency produced upon ionization and the difference between adiabatic and vertical ionization energies. The use of such a correlation in the analysis of vibrational fine structure is exemplified by considering the examples of methylfluoride, 1,1-difluoroethylene, sulphur hexafluoride, ketene and pyrazine. A comparison between the p.e. spectra of butadiene, acrolein and glyoxal is used to indicate the utility of the method in creating energy level diagrams for related series of compounds.


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