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The unoccupied conduction band and the occupied valence band of α- and β-brass (Cu-Zn) have been studied by inverse photoemission and photoemission spectroscopy. The experimental spectra have been interpreted with the help of calculations based on full potential linearized augmented plane wave method using density functional theory. The modification of the conduction and valence bands between α- and β-brass is related to the change in structure and increase in Zn content. For CuZn, the density of states exhibits a monotonic decrease across the Fermi level (EF) with a dip at about 2 eV above EF, but no evidence of a minimum representing a pseudogap is observed at EF.

The influence of $sp\text{\ensuremath{-}}d$ hybridization on the electronic structure of different Al-Mn alloys has been studied by photoelectron spectroscopy. Experimental evidence of a pseudogap in a crystalline binary Hume-Rothery alloy is provided. The pseudogap varies systematically with Mn concentration. The $sp\text{\ensuremath{-}}d$ hybridization alone, even in the absence of Hume-Rothery mechanism, can produce the pseudogap. Existence of the pseudogap, suppression of the $\mathrm{Mn}\phantom{\rule{0.2em}{0ex}}2p$ satellite, and decrease in the Doniach-\ifmmode \check{S}\else \v{S}\fi{}unji\ifmmode \acute{c}\else \'{c}\fi{} asymmetry parameter are the consequences of the $sp\text{\ensuremath{-}}d$ hybridization. An in situ method of preparing these alloys by annealing a Mn adlayer on Al(111) is presented.

Using high-resolution core-level photoelectron spectroscopy and modified Anderson impurity model calculations, we study the $\mathrm{Mn}\phantom{\rule{0.2em}{0ex}}2p$ spectrum of manganese metal and resolve the current debate about its spectral shape. An unusual satellite feature, $1\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ from the main peak, is observed in the $\mathrm{Mn}\phantom{\rule{0.2em}{0ex}}2{p}_{3∕2}$ spectrum of a thick Mn layer grown on Al. It originates from intra-atomic multiplet effect related to Mn atoms with large local moment. The satellite decreases in intensity for thin Mn layers and for Al deposition on bulklike Mn because of enhanced $\mathrm{Mn}\phantom{\rule{0.2em}{0ex}}3d$ hybridization with Al $s,p$ bandlike states. The reason for the absence of a charge-transfer satellite is discussed.

We report x-ray photoelectron spectroscopy (XPS) study of Na and K adlayers on icosahedral ${\mathrm{Al}}_{70.5}{\mathrm{Pd}}_{21}{\mathrm{Mn}}_{8.5}$ $(i\text{\ensuremath{-}}\mathrm{Al}\text{\ensuremath{-}}\mathrm{Pd}\text{\ensuremath{-}}\mathrm{Mn})$ quasicrystal. The Na $1s$ core-level exhibits a continuous linear shift of $0.8\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ towards lower binding energies (BE) with increasing coverage up to one monolayer (ML) saturation coverage. In the case of $\mathrm{K}∕i\text{\ensuremath{-}}\mathrm{Al}\text{\ensuremath{-}}\mathrm{Pd}\text{\ensuremath{-}}\mathrm{Mn}$, a similar linear shift in the K $2p$ spectra towards lower BE is observed. In both cases, the plasmon related loss features are observed only above 1 ML. The substrate core-level peaks, such as Al $2p$, do not exhibit any shift with the adlayer deposition up to the highest coverage. Based on these experimental observations and previous studies of alkali metal growth on metals, we conclude that below 1 ML, both Na and K form a dispersed phase on $i\text{\ensuremath{-}}\mathrm{Al}\text{\ensuremath{-}}\mathrm{Pd}\text{\ensuremath{-}}\mathrm{Mn}$ and there is hardly any charge transfer to the substrate. The variation of the adlayer and substrate core-level intensities with coverage indicates layer by layer growth.

The energies of ion migration in KCl through isolated vacancies, vacancy pairs, trivacancies, and interstitials have been investigated. A path-variation study in the case of vacancy and vacancy-pair mechanisms show that the usually assumed path in the (100) plane is the most probable one. Trivacancies do not seem to contribute to high-temperature conduction. On the other hand, the formation of a Frenkel defect pair and interstitialcy migration through a collinear path may be responsible for the nonrandom deviations in ionic conductivity data at high temperatures.