A theoretical study of the nucleation, size, and structure of diamond phase carbon clusters on Si~111! substrates is presented. Molecular mechanics analysis has been utilized to predict energetically and entropically feasible pathways for nucleation of the carbon clusters. Several mechanistic pathways for nucleation of carbon clusters are examined with CH3 and/or C2H2 as the nucleation precurso...

In a previous communication, we showed that a single Au atom behaves like H in its bonding to Si in a series of Si-Au clusters, SiAu(n) (n = 2-4) (Kiran et al. Angew. Chem., Int. Ed. 2004, 43, 2125). In this article, we show that the H analogy of Au is more general. We find that the chemical bonding and potential energy surfaces of two disilicon Au clusters, Si(2)Au(2) and Si(2)Au(4), are analo...

XMM-Newton observations of 19 galaxy clusters are used to measure the elemental abundances and their spatial distributions in the intracluster medium. The sample mainly consists of X-ray bright and relaxed clusters with a cD galaxy. Along with detailed Si, S and Fe radial abundance distributions within 300-700 kpc in radius, the O abundances are accurately derived in the central region of the c...

XMM-Newton observations of 19 galaxy clusters are used to measure the elemental abundances and their spatial distributions in the intracluster medium. The sample mainly consists of X-ray bright and relaxed clusters with a cD galaxy. Along with detailed Si, S and Fe radial abundance distributions within 300-700 kpc in radius, the O abundances are accurately derived in the central region of the c...

Clusters in the (Be, B, C)@Si(n)((0,1,2+)) (n = 6-10) series, isoelectronic to Si(n)(2-), present multiple symmetric structures, including rings, cages and open structures, which the doping atom stabilizes using contrasting bonding mechanisms. The most striking feature of these clusters is the absence of electron transfer (for Be) or even the inversion (for B and C) in comparison to classic end...

The electronic and structural properties of semiconductor clusters are examined using pseudopotentials and a real space method. Examples of this method are applied to predict the photoemission spectra, the vibrational modes, and the polarizabilities of Si and Ge clusters.

Iron-functionalized disordered mesoporous silica (FeKIL-2) is a promising, environmentally friendly, cost-effective and highly efficient catalyst for the elimination of volatile organic compounds (VOCs) from polluted air via catalytic oxidation. In this study, we investigated the type of catalytically active iron sites for different iron concentrations in FeKIL-2 catalysts using advanced charac...

In this paper atom probe tomography is used to explore early stage clustering in aluminum alloys. Two novel concepts for a modi cation of clustering are discussed. Control of early stage clustering is welcome from an application point of view since clustering deteriorates strength evolution during the industrial heat treatment of the important class of Al Mg Si precipitation-hardenable alloys. ...

In this paper, the relationship between the liquid structure and the corresponding solidified microstructure of an Al-Si-Mg-P alloy was studied. Experimental results show that Mg can reduce the phosphorous-modification effect if it was added after adding Al-P alloy. However, when it is added before adding Al-P alloy, Mg has no effect on the phosphorous-modification. It is considered that the di...

Silicon (Si) cage clusters, i.e., Si fullerenes doped with argon (Ar) atom are formed using a Si plasma. The Si plasma is generated by irradiation of an electron beam to a Si lump in Ar gas atmosphere. When the Ar gas pressure is 0.08 Pa or more, the Ar plasma is also generated by the collision of the electron beam and superimposed upon the Si plasma. The ionized Si agglutinates in the diffusio...