Theoretical studies photoelectron spectra

The thermal decomposition of some 3,5-disubstituted-l,2,4-thiadiazoles has been studied and some nonisothermal kinetic parameters have been reported <1986MI239>. Polarographic measurements of a series of methylated 5-amino-l,2,4-thiadiazoles show that thiadiazoles are not reducible in methanolic lithium chloride solution, while thiadiazolines are uniformily reduced at 0.5 = — 1.6 0.02 V. This technique has been used to assign structures to compounds which may exist theoretically as either thiadiazoles or thiadiazolines <1984CHEC(6)463>. The photoelectron spectrum for 1,2,4-thiadiazole has been published <1996CHEC-II(4)307>. 

With metal clusters it is even harder than in other fields of inorganic chemistry to substantiate theoretical results by energy measurements. Only two such measurements have come to the attention of the author — the photoelectron spectrum of [CpFe(C0)]4 370) andbond energy determinations in 03(00)9CX-compounds 187). However, a considerable number of papers deal with metal-metal bonding in, and the symmetry properties of, clusters as related to their stoichiometry and their electron count. These studies have confirmed the wide apphcability of the simple 18-electron rule in predicting metal-metal bonds and structures, but they have also led to an understanding of the limits of this rule for clusters with more than four metal atoms. 

Subsequently, Grunthaner reexamined the ESCA spectrum of the 2-norbornyl cation on a higher-resolution X-ray photoelectron spectrometer using highly efficient vacuum techniques.884 The spectrum closely matches the previously published spectra. Furthermore, the reported ESCA spectral results are consistent with the theoretical studies of Allen and co-workers885 on the classical and nonclassical norbomyl cation at the STO-3G and STO-4.31G levels. Using the parameters obtained by Allen and co-workers, Clark and co-workers were able to carry out a detailed... 

The photoelectron spectrum was initially interpreted (29e) in terms of trapped valencies but a theoretical study by Hush (67) has shown that a delocalized description is equally consistent with the data available so far. Infrared data are still under discussion, but the Raman spectrum has been interpreted (29f) in terms of localization. It does seem clear that the rate of valence interchange according to Eq. (1) is rapid compared with the NMR time scale (29b) the possibility remains that the rate may be comparable with the frequencies of certain bond vibrations. 

HBr Theoretical study of the intramolecular dynamics of molecular ions. Application to the photoelectron spectrum of HBr (A S ) 983... 

In the structure 31 (X = Si) strong electron donation from the Si-C bond to cyclopropyl was proposed to occur based on the electronic spectra of charge transfer complexes and IR and Raman spectra and a similar interaction for the Sn analog was deduced from the UV photoelectron spectrum and proposed to involve the conformation indicated. Structural studies of these compounds to determine if these conformations are actually favored could be most informative, as would investigation of conformationally fixed compounds and detailed theoretical calculations. 

The aim of the present work is to perform a detailed theoretical study of the electronic structures of actinyl nitrates. Relativistic effects are remarkable in the electronic structure and chemical bonding of heavy atoms such as actinide elements[6j. In our previous study, we applied the relativistic discrete variational Dirac-Fock-Slater(DV-DFS) method to study of the electronic structure of uranyl nitrate dihydrate[7]. The accuracy of the DV-DFS method was demonstrate by its ability to reproduce the uranyl nitrate dihydrate experimental X-ray photoelectron spectrum. 

The benzene radical cation (Bz+) represents a prototype organic radical cation and has been studied extensively in the literature, both theoretically and experimentally. We mention early and more recent studies of its electronic structure,the photoelectron spectrum of benzene, including its vibrational structure and the high-resolution... 

The absorption spectrum of 7 in aqueous acidic solutions has also been detected. The vertical gas-phase ionization potential /p of benzene was measured from the He(I) photoelectron spectrum as 9.23 ev.37e standard anodic peak potential Ep could not be measured directly but was estimated from data for alkyl-substituted benzenes as 2.86 V vs NHE. Jahn-Teller distortion in 7 has been reviewed, and the high-resolution state-to-state threshold photoionization spectrum of benzene gives the shape of 7 8 and diminished significantly the mystery regarding the structure. The geometries, hyperfine structure, and relative stabilities of the two mono-deuterated Jahn—Teller-distorted ions CeHsD were examined theoretically and experimentally. EPR and ENDOR studies showed the toluene radical cation possessed the B2g structure. The IR spectra of the two Jahn—Teller forms of 7 were also calculated. On the basis of the calculated energy levels, both 7 and 8 have been classified as antiaromatic. ... 

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