Electronic structure of chromium oxides, CrOn− and CrOn (n=1–5) from photoelectron spectroscopy and density functional theory calculations

Abstract

The electronic structure of CrO n Ϫ and CrO n (nϭ1-5) was investigated using anion photoelectron spectroscopy and density functional theory. Photoelectron spectra of CrO n Ϫ were obtained at several photon energies and yielded electron affinities, vibrational and electronic structure information about the neutral CrO n species. Density functional theory calculations were carried out for both the neutrals and anions and were used to interpret the experimental spectra. Several low-lying electronic states of CrO were observed and assigned from photodetachment of the CrO Ϫ ground state (6 ͚ ϩ) and an excited state (4 ͟), which is only 0.1 eV higher. The main spectral features of CrO 2 Ϫ were interpreted based on a C 2v CrO 2 Ϫ (4 B 1). A very weak Cr͑O 2) Ϫ isomer was also observed with lower electron binding energies. Relatively simple and vibrationally resolved spectra were observed for CrO 3 Ϫ , which was determined to be D 3h. The CrO 3 neutral was calculated to be C 3v with the Cr atom slightly out of the plane of the three O atoms. The spectrum of CrO 4 Ϫ revealed a very high electron binding energy. Several isomers of CrO 4 Ϫ were predicted and the ground state has a distorted tetrahedral structure (C 2) without any O-O bonding. Only one stable structure was predicted for CrO 5 Ϫ with a superoxo O 2 bonded to a C 3v CrO 3 .

Peroxides and Chromium Compounds – The Ether Test for Identity

“…The configuration of CrO 5 · SOLV differs from the geometry of unsolvated CrO 5 . According to a photoelectron spectroscopy study [39], free CrO 5 contains one cyclic and one open-chain peroxide moiety. For H 2 O as a ligand the hitherto "belief" of CrO(O 2 ) 2 · H 2 O being blue perchromic acid [33], has been accepted generally [34] owing to [31].…”

Studies of the Surface Reaction Mechanisms of Pb-3 wt%Sn-0.5 wt%Ag Anode in CrO3Solutions

“…This improves the Cr 2 O 7 2− ion adsorption on the lead alloy surface. G. L. Gutsev et al 31 have studied CrO 3 shows a very high electron affinity (EA), which indicates that it should be a strong oxidizing agent. Species with large EA's have the ability to trap free electrons in excited gases and form extremely stable negative ions, for example CrO n − (n = 1-5), which present the different energy feature.…”

Decreasing the Effect of Ultra Violet Ray on Polypropylene by Using Chromium Tri-oxide

“…In these industries, CrO 3 is used for plating the chromium on car body and other auto components. Chromium trioxide shows a very high electron affinity, which indicates that it should be a strong oxidizing agent which enables it to be used in various pharmaceutical and chemical industries [10]. It is also reported that CrO 3 complexes exhibit the antibacterial activity against Pseudomonas aeruginosa bacteria.…”