The He(I) and X-ray photoelectron spectra of p-N,N-dimethylaminobenzalmalonitrile

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.

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


2018 ◽  
Vol 196 ◽  
pp. 04005
Author(s):  
Irina Stepina ◽  
Irina Kotlyarova

The difficulty of wood protection from biocorrosion and fire is due to the fact that modifiers in use are washed out from the surface of the substrate under the influence of environmental factors. This results in a rapid loss of the protective effect and other practically important wood characteristics caused by the modification. To solve this problem is the aim of our work. Here, monoethanolaminoborate is used as a modifier, where electron-donating nitrogen atom provides a coordination number equal to four to a boron atom, which determines the hydrolytic stability of the compounds formed. Alpha-cellulose ground mechanically to a particle size of 1 mm at most was used as a model compound for the modification. X-ray photoelectron spectra were recorded on the XSAM-800 spectrometer (Kratos, UK). Prolonged extraction of the modified samples preceded the registration of the photoelectron spectra to exclude the fixation of the modifier molecules unreacted with cellulose. As a result of the experiment, boron and nitrogen atoms were found in the modified substrate, which indicated the hydrolytic stability of the bonds formed between the modifier molecules and the substrate. Therefore monoethanolaminoborate can be considered as a non-extractable modifier for wood-cellulose materials.


Author(s):  
Mariola Kądziołka-Gaweł ◽  
Maria Czaja ◽  
Mateusz Dulski ◽  
Tomasz Krzykawski ◽  
Magdalena Szubka

AbstractMössbauer, Raman, X-ray diffraction and X-ray photoelectron spectroscopies were used to examine the effects of temperature on the structure of two aluminoceladonite samples. The process of oxidation of Fe2+ to Fe3+ ions started at about 350 °C for the sample richer in Al and at 300 °C for the sample somewhat lower Al-content. Mössbauer results show that this process may be associated with dehydroxylation or even initiate it. The first stage of dehydroxylation takes place at a temperature > 350 °C when the adjacent OH groups are replaced with a single residual oxygen atom. Up to ~500 °C, Fe ions do not migrate from cis-octahedra to trans-octahedra sites, but the coordination number of polyhedra changes from six to five. This temperature can be treated as the second stage of dehydroxylation. The temperature dependence on the integral intensity ratio between bands centered at ~590 and 705 cm−1 (I590/I705) clearly reflects the temperature at which six-coordinated polyhedra are transformed into five-coordinated polyhedra. X-ray photoelectron spectra obtained in the region of the Si2p, Al2p, Fe2p, K2p and O1s core levels, highlighted a route to identify the position of Si, Al, K and Fe cations in a structure of layered silicates with temperature. All the measurements show that the sample with a higher aluminum content and a lower iron content in octahedral sites starts to undergo a structural reorganization at a relatively higher temperature than the less aluminum-rich sample does. This suggests that iron may perform an important role in the initiation of the dehydroxylation of aluminoceladonites.


2012 ◽  
Vol 90 (1) ◽  
pp. 39-43 ◽  
Author(s):  
X. Xiang ◽  
D. Chang ◽  
Y. Jiang ◽  
C.M. Liu ◽  
X.T. Zu

Anatase TiO2 thin films are deposited on K9 glass samples at different substrate temperatures by radio frequency magnetron sputtering. N ion implantation is performed in the as-deposited TiO2 thin films at ion fluences of 5 × 1016, 1 × 1017, and 5 × 1017 ions/cm2. X-ray diffraction, atomic force microscope, X-ray photoelectron spectroscopy (XPS), and UV–visible spectrophotometer are used to characterize the films. With increasing N ion fluences, the absorption edges of anatase TiO2 films shift to longer wavelengths and the absorbance increases in the visible light region. XPS results show that the red shift of TiO2 films is due to the formation of N–Ti–O compounds. As a result, photoactivity is enhanced with increasing N ion fluence.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Patcharanan Junploy ◽  
Titipun Thongtem ◽  
Somchai Thongtem ◽  
Anukorn Phuruangrat

SrSn(OH)6 precursors synthesized by a cyclic microwave radiation (CMR) process were calcined at 900°C for 3 h to form rod-like SrSnO3. Further, the rod-like SrSnO3 and AgNO3 in ethylene glycol (EG) were ultrasonically vibrated to form rod-like Ag/SrSnO3 composites, characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron microscopy (EM), Fourier transform infrared (FTIR) spectroscopy, and UV-visible analysis. The photocatalyses of rod-like SrSnO3, 1 wt%, 5 wt%, and 10 wt% Ag/SrSnO3 composites were studied for degradation of methylene blue (MB, C16H18N3SCl) dye under ultraviolet (UV) radiation. In this research, the 5 wt% Ag/SrSnO3 composites showed the highest activity, enhanced by the electron-hole separation process. The photoactivity became lower by the excessive Ag nanoparticles due to the negative effect caused by reduction in the absorption of UV radiation.


2015 ◽  
Vol 185 ◽  
pp. 471-479 ◽  
Author(s):  
B. P. Jarman ◽  
F. Cucinotta

The presented study reports the use of photoactive templating structures for the design of porous frameworks with built-in optical functionalities. The materials have been synthesised and characterised using powder X-ray diffractometry, UV-visible absorption and emission spectroscopy. The latter shows that, by varying the relative amount of an amphiphilic chromophore in the micellar templates, it is possible to tune the light absorption and emission properties over the visible spectrum, by means of controlling the molecular organisation and the excitonic coupling of aggregated species. This enables versatile solid materials that can be used as optical components for light-harvesting and converting systems to be obtained .


Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 202
Author(s):  
Miranda Martinez ◽  
Anil R. Chourasia

The Ti/SnO2 interface has been investigated in situ via the technique of x-ray photoelectron spectroscopy. Thin films (in the range from 0.3 to 1.1 nm) of titanium were deposited on SnO2 substrates via the e-beam technique. The deposition was carried out at two different substrate temperatures, namely room temperature and 200 °C. The photoelectron spectra of tin and titanium in the samples were found to exhibit significant differences upon comparison with the corresponding elemental and the oxide spectra. These changes result from chemical interaction between SnO2 and the titanium overlayer at the interface. The SnO2 was observed to be reduced to elemental tin while the titanium overlayer was observed to become oxidized. Complete reduction of SnO2 to elemental tin did not occur even for the lowest thickness of the titanium overlayer. The interfaces in both the types of the samples were observed to consist of elemental Sn, SnO2, elemental titanium, TiO2, and Ti-suboxide. The relative percentages of the constituents at the interface have been estimated by curve fitting the spectral data with the corresponding elemental and the oxide spectra. In the 200 °C samples, thermal diffusion of the titanium overlayer was observed. This resulted in the complete oxidation of the titanium overlayer to TiO2 upto a thickness of 0.9 nm of the overlayer. Elemental titanium resulting from the unreacted overlayer was observed to be more in the room temperature samples. The room temperature samples showed variation around 20% for the Ti-suboxide while an increasing trend was observed in the 200 °C samples.


1977 ◽  
Vol 1 (1) ◽  
pp. 25-32 ◽  
Author(s):  
P.A. Zhdan ◽  
G.K. Boreskov ◽  
A.I. Boronin ◽  
A.P. Schepelin ◽  
W.F. Egelhoff ◽  
...  

2020 ◽  
Vol 22 (5) ◽  
pp. 2693-2703 ◽  
Author(s):  
Marta L. Vidal ◽  
Anna I. Krylov ◽  
Sonia Coriani

Ionization energies and Dyson orbitals within frozen-core core–valence separated equation-of-motion coupled cluster singles and doubles (fc-CVS-EOM-CCSD) enable efficient and reliable calculations of standard XPS and of UV-pump/XPS probe spectra.


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


Sign in / Sign up

Export Citation Format

Share Document