ELECTRONIC STRUCTURE OF ASSEMBLED CLUSTERS WITHIN THE STABILIZED JELLIUM MODEL

1996 ◽  
Vol 03 (01) ◽  
pp. 1001-1006
Author(s):  
HENRIK GRÖNBECK ◽  
ARNE ROSÉN

The electronic structure of assembled closed shell clusters have been analyzed using a spherical, stabilized jellium description of the clusters. The effects of including stabilization terms to the jellium model were investigated by calculating the properties of cluster dimers, (Na20)2 and ( Cu 20)2. In addition, the electronic properties of a material consisting of closed shell Al 12X clusters, where X is C or Si, were investigated using a model of six clusters. The large gap at the Fermi level present for the building blocks was also found to appear for the cluster-assembled material. The binding energy of the clusters in the cluster-assembled material was compared with that of an atomic Al lattice.

2003 ◽  
Vol 802 ◽  
Author(s):  
John J. Joyce ◽  
John M. Wills ◽  
Tomasz Durakiewicz ◽  
Elzbieta Guziewicz ◽  
Martin T. Butterfield ◽  
...  

ABSTRACTThe electronic structure of δ-phase Pu metal and the Pu-based superconductor PuCoGa5 is explored using photoelectron spectroscopy and a novel theoretical scheme. Excellent agreement between calculation and experiment defines a path forward for understanding electronic structure aspects of Pu-based materials. The photoemission results show two separate regions of 5f electron spectral intensity, one at the Fermi energy and another centered 1.2 eV below the Fermi level. A comparison is made between the photoemission data and five computational schemes for δ-Pu. The results for δ-Pu and PuCoGa5 indicate 5f electron behavior on the threshold between localized and itinerant and a broader framework for understanding the fundamental electronic properties of the Pu 5f levels in general within two configurations, one localized and one itinerant.


1974 ◽  
Vol 29 (5) ◽  
pp. 768-772 ◽  
Author(s):  
G. Ertl ◽  
K. Wandelt

Abstract Variations of the electronic properties of nickel during the first stages of oxidation were studied by means of the soft x-ray appearance potential spectroscopy (APS). The spectra consist of a superposition of contributions from metallic nickel and from NiO and yield no evidence for a continuous change of the oxidation state of the Ni atoms. The binding energy of the 2p3/2-electrons in metallic nickel was found to be 851 eV and is increased in NiO by 1.4 eV. It is concluded from the shape of the APS peaks that with Ni above the Fermi level 3d- and 4s-bands are superimposed whereas with NiO these are separated in energy.


Open Physics ◽  
2010 ◽  
Vol 8 (3) ◽  
Author(s):  
Igor Shein ◽  
Alexander Ivanovskii

AbstractFirst principle FLAPW-GGA calculations have been performed with the purpose to understand the effect of Ti-doping on the electronic properties for the newly discovered tetragonal iron arsenide-oxide Sr4Sc2Fe2As2O6 (abbreviated as FeAs42226) as the possible parent phase for the new FeAs superconductors. Our results show that the insertion of Ti into Sc sublattice of this five-component iron arsenide-oxide phase leads to the resolute change of electronic structure of FeAs42226. Namely, the insulating oxygen-containing [Sr4Sc2O6] blocks in Ti-doped FeAs42226 became conducting, and this differs essentially from the known picture for all others FeAs superconductors where the conducting [Fe2As2] blocks are alternated with insulating blocks. Moreover in sharp contrast with FeAs-based superconductors with Fe 3d bands near the Fermi level, for Ti-doped FeAs42226 in this region the Ti 3d states are dominated, whereas the Fe 3d states are suppressed.


2015 ◽  
Vol 754-755 ◽  
pp. 762-765
Author(s):  
A. Chik ◽  
S. Saad ◽  
R.M. Zaki ◽  
F. Che Pa ◽  
C.K. Yeoh

The electronic structure of the perovskite manganites LaMnO3 and La2/3 Al1/3 MnO3 was presented. The calculations were made within density functional theory (DFT) and PBE exchange correlations energy approximation. It was found that inclusion of Al dopants add additional states near the Fermi level and decreasing the resistivity values for all temperature range.


1994 ◽  
Vol 01 (04) ◽  
pp. 641-644 ◽  
Author(s):  
R.B. PATEL ◽  
A.J. LIDDIARD ◽  
M.D. CRAPPER

Angle-resolved photoemission has been used to investigate the electronic structure of Pt 3 Cr . Experimental band structure has been calculated assuming a free-electron final state. Constant initial state measurements indicate that Pt and Cr d-bands both lie between the Fermi level and 7 eV binding energy.


2001 ◽  
Vol 66 (1) ◽  
pp. 139-154 ◽  
Author(s):  
M. Fátima C. Guedes Da Silva ◽  
Luísa M. D. R. S. Martins ◽  
João J. R. Fraústo Da Silva ◽  
Armando J. L. Pombeiro

The organonitrile or carbonyl complexes cis-[ReCl(RCN)(dppe)2] (1) (R = 4-Et2NC6H4 (1a), 4-MeOC6H4 (1b), 4-MeC6H4 (1c), C6H5 (1d), 4-FC6H4 (1e), 4-ClC6H4 (1f), 4-O2NC6H4 (1g), 4-ClC6H4CH2 (1h), t-Bu (1i); dppe = Ph2PCH2CH2PPh2), or cis-[ReCl(CO)(dppe)2] (2), as well as trans-[FeBr(RCN)(depe)2]BF4 (3) (R = 4-MeOC6H4 (3a), 4-MeC6H4 (3b), C6H5 (3c), 4-FC6H4 (3d), 4-O2NC6H4 (3e), Me (3f), Et (3g), 4-MeOC6H4CH2 (3h); depe = Et2PCH2CH2PEt2), novel trans-[FeBr(CO)(depe)2]BF4 (4) and trans-[FeBr2(depe)2] (5) undergo, as revealed by cyclic voltammetry at a Pt-electrode and in aprotic non-aqueous medium, two consecutive reversible or partly reversible one-electron oxidations assigned as ReI → ReII → ReIII or FeII → FeIII → FeIV. The corresponding values of the oxidation potentials IE1/2ox and IIE1/2ox (waves I and II, respectively) correlate with the Pickett's and Lever's electrochemical ligand and metal site parameters. This allows to estimate these parameters for the various nitrile ligands, depe and binding sites (for the first time for a FeIII/IV couple). The electrochemical ligand parameter show dependence on the "electron-richness" of the metal centre. The values of IE1/2ox for the ReI complexes provide some supporting for a curved overall relationship with the sum of Lever's electrochemical ligand parameter. The Pickett parametrization for closed-shell complexes is extended now also to 17-electron complexes, i.e. with the 15-electron ReII and FeIII centres in cis-{[ReCl(dppe)2]}+ and trans-{FeBr(depe)2}2+, respectively.


2021 ◽  
Author(s):  
Max Schütz ◽  
Christian Gemel ◽  
Maximilian Muhr ◽  
Christian Jandl ◽  
Samia Kahlal ◽  
...  

Cu/Al cluster growth reactions leading to open- and closed-shell superatoms are investigated. Therein, LIFDI-MS is presented as a powerful technique for the in situ detection of cluster identities and reactivity patterns.


2021 ◽  
Vol 9 (36) ◽  
pp. 20653-20663
Author(s):  
Johanna Eichhorn ◽  
Simon P. Lechner ◽  
Chang-Ming Jiang ◽  
Giulia Folchi Heunecke ◽  
Frans Munnik ◽  
...  

The (opto)electronic properties of Ta3N5 photoelectrodes are often dominated by defects, but precise control of these defects provides new insight into the electronic structure, photocarrier transport, and photoelectrochemical function.


2014 ◽  
Vol 895 ◽  
pp. 420-423 ◽  
Author(s):  
Sathya Sheela Subramanian ◽  
Baskaran Natesan

Structural optimization, magnetic ground state and electronic structure calculations of tetragonal PbMnO3have been carried out using local density approximation (LDA) implementations of density functional theory (DFT). Structural optimizations were done on tetragonal P4mm (non-centrosymmetric) and P4/mmm (centrosymmetric) structures using experimental lattice parameters and our results indicate that P4mm is more stable than P4/mmm. In order to determine the stable magnetic ground state of PbMnO3, total energies for different magnetic configurations such as nonmagnetic (NM), ferromagnetic (FM) and antiferromagnetic (AFM) were computed for both P4mm and P4/mmm structures. The total energy results reveal that the FM non-centrosymmetric structure is found to be the most stable magnetic ground state. The electronic band structure, density of states (DOS) and the electron localization function (ELF) were calculated for the stable FM structure. ELF revealed the distorted non-centrosymmetric structure. The band structure and DOS for the majority spins of FM PbMnO3showed no band gap at the Fermi level. However, a gap opens up at the Fermi level in minority spin channel suggesting that it could be a half-metal and a potential spintronic candidate.


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