Electronic structure inverse photoemission

There is much consensus between the cluster and periodic modeling results compared to experiment, especially in regards to the band structure and 0 K magnetism. Deductions regarding the electronic structure from photoemission and inverse photoemission experiments indicate that the upper valence band consists of a wide, bonding O 2p-Fe 3d band, and the conduction band is a more narrow antibonding O 2p... 

At a surface, not only can the atomic structure differ from the bulk, but electronic energy levels are present that do not exist in the bulk band structure. These are referred to as surface states . If the states are occupied, they can easily be measured with photoelectron spectroscopy (described in section A 1.7.5.1 and section Bl.25.2). If the states are unoccupied, a teclmique such as inverse photoemission or x-ray absorption is required [22, 23]. Also, note that STM has been used to measure surface states by monitoring the tunnelling current as a fiinction of the bias voltage [24] (see section BT20). This is sometimes called scamiing tuimelling spectroscopy (STS). 

The problem of first-principles calculations of the electronic structure of solid surface is usually formatted as a problem of slabs, that is, consisting of a few layers of atoms. The translational and two-dimensional point group symmetry further reduce the degrees of freedom. Using modern supercomputers, such first-principles calculations for the electronic structure of solid surfaces have produced remarkably reproducible and accurate results as compared with many experimental measurements, especially angle-resolved photoemission and inverse photoemission. 

The measurement of tunnelling spectra in a scanning tunnelling microscope offers the potential of measuring the local density of states at spatially defined sites whose topography can be established at an atomic scale by STM. This information is only available however at the price of losing the information about the k-dependence of electronic states that is available in photoemission and inverse photoemission. In particular STS offers the prospect of measuring local densities of states at defect sites whose real space atomic structure can be established by STM. 

J. H. Weaver, Electronic Structures of Cso. C70, and the Fullerides Photoemission and Inverse Photoemission Studies, J. Phys. Chem. Solids 53, 1433-1447 (1992). 

Traving M, Boehme M, Kipp L, Skibowski M, Starrost F, Krasovskii E E, Perlov A and Schattke W1997 Electronic structure of WSe2 a combined photoemission and inverse photoemission study Phys. Rev. B 55 10 392-9... 

Weaver J H 1992 Electronic structures of CgQ, C- q and the fullerides—photoemission and inverse photoemission studies J. Phys. Chem. Solids 1433... 

Paze, C., Bordiga, S., Lamberti, C., Salvalaggio, M., Zecchina, A., Bellussi, G. (1997). Acidic Properties of H-p Zeolite as Probed by Bases with Proton Affinity in the 118-204 kcal moH Range A FTIR Investigation. Journal of Physical Chemistry B, Vol.101, No.24, (June 1997), pp. 4740-4751, ISSN 1520-6106 Peri, J.B. (1965). A Model for the Surface of y-Alumina. Journal of Physical Chemistry, VoL69, No.l, (January 1965), pp. 220-230, ISSN 0022-3654 Pillo, T., Zimmermann, R., Steiner, P., Hufner, S. (1997). The Electronic Structure of PdO Found by Photoemission (UPS and XPS) and Inverse Photoemission (BIS). Journal of Physics Condensed Matter, Vol.9, No.l9, (May 1997), pp. 3987-3999, ISSN 0953-8984 Rakai, A., Tessier, D., Bozon-Verduraz, F. (1992). Palladium-Alumina Catalysts - a Diffuse Reflectance Study. New Journal of Chemistry, Vol.16, No.8-9, (August-September 1992), pp. 869-875, ISSN 1144-0546... 

The various versions of inverse photoemission have been applied to purely basic problems, just as with UPS and ELS. Recent typical examples include the bonding of Hj on Ni (110) 3I4J the oxidation of a titanium thin film [315] the effects on Ht chemisorption of a monolayer of nickel on Cu (111) [316] unoccupied electronic structure in La2Cu04 [317] and in Bi2Sr2CaCu20g [318] and KRIPES studies of the Ge (113) (2x1) [319] and TiNo.8.1 (100) [320] surfaces. 

Nishi, T., Iwahashi, T., Yamane, H., Ouchi, Y, Kanai, K. and Seki, K., Electronic structures of ionic liquids and studied by ultraviolet photoemission, inverse photoemission, and nearedge X-ray absorption fine structure spectroscopies, Chem. Phys. Lett. 455, 213-217 (2008). 

A similar two-peak structure is seen in the inverse photoemission (bremsstrahlung isochromat spectroscopy (BIS)) spectra of cerium (Land et al. 1981) and several of its compounds (Allen et al. 1983). (In a BIS experiment, one adds an electron to the system.) The first peak is just above p ( 0.5eV) and is dominant in the more itinerant cerium compounds. The second peak is located 4-5eV above the pand is due to localized f -> P transitions. The BIS spectrum in certain ways thus mirrors what is seen in the photoemission spectrum. With this in mind, it was decided to apply the techniques of the preceding sections to determine the inverse photoemission spectrum of CeP (Norman, 1985). 

Fig. 2. Photoemission and inverse-photoemission spectra of SrVOa and CaVOa in the V-3d hand region compared with an LDA hand-structure calculation hy Takegahara K (1994) J Electron Spectrosc Relat Phenon 66 303 after [11]...

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