Electronic Properties of Bulk

Here, we discuss in some detail the DFT implementation in our computer program, since only in the last few years DFT is becoming more familiar to the chemists community, as opposite to the physicists community, where it was used routinely for the last thirty years for obtaining structural and electronic properties of bulk solids and surfaces [19],... 

F. R. Sensato, R. Custodio, M. Calatayud, A. Beltran, J. Andres, J. R. Sambrano, and E. Longo, Surf. Sci., 511,408 (2002). Periodic Study on the Structural and Electronic Properties of Bulk, Oxidized and Reduced Sn02 (110) Surfaces and the Interaction with 0 . 

Menendez-Proupin, E. and Gutierrez, G. (2005) Electronic properties of bulk Y-AI2O3. Phys. Rev. B, 72, 035116. 

Frenzel, J., Oliveira, A.F., Duarte, H.A., Heine, T. Seifert, G. (2005) Structural and electronic properties of bulk gibbsite and gibbsite surfaces. Zeitschrift Fur Anorganische Und Allgemeine Chemie, 631,1267-1271. 

Wachutka G, Fleszar A, Maca F and Scheffler M 1992 Self-consistent Green-function method for the calculation of electronic properties of localized defects at surfaces and in the bulk J. Phys. Condens Matter A 2831 Bormet J, Neugebauer J and Scheffler M 1994 Chemical trends and bonding mechanisms for isolated adsorbates on Al(111) Phys. Rev. B 49 17 242... 

The chemical and electronic properties of elements at the interfaces between very thin films and bulk substrates are important in several technological areas, particularly microelectronics, sensors, catalysis, metal protection, and solar cells. To study conditions at an interface, depth profiling by ion bombardment is inadvisable, because both composition and chemical state can be altered by interaction with energetic positive ions. The normal procedure is, therefore, to start with a clean or other well-characterized substrate and deposit the thin film on to it slowly at a chosen temperature while XPS is used to monitor the composition and chemical state by recording selected characteristic spectra. The procedure continues until no further spectral changes occur, as a function of film thickness, of time elapsed since deposition, or of changes in substrate temperature. 

A large body of work with particular reference to the mimicry of mononuclear zinc enzymes has utilized tris(pyrazolyl)borate ligands. This ligand class offers a facial coordination mode of three pyrazole A-donors and can be functionalized in the three and five positions on the rings to increase steric bulk and vary the electronic properties of the ligand. The synthesis and complex formation with these ligands has been extensively reviewed.2,21 219... 

Perhaps of greater interest to us are results derived by the same authors71 that relate surface and bulk electronic properties of jellium. Considering two jellium slabs, one extending from —L to -D and the other from D to L, they calculated the force per unit area exerted by one on the other. According to the Hellmann-Feynman theorem, this is just the sum of the electric fields acting... 

The purpose of this section is to point out how the electronic properties of the surface differ from those of the bulk. In the next section we explain how the electronic properties are involved in chemisorption, and why promoters can help molecules to chemisorb and react on surfaces [6-8]. 

Ozensoy et al.127 also used PM-IRAS to study the CO adsorption behavior on Si02-supported Pd clusters. As mentioned above, these crystalline, ultrathin silica films possess the structural and electronic properties of the bulk analogues, but are thin enough to permit the use of vibrational and electronic spectroscopic techniques (and tunneling microscopy) without charging.39 40 As with the... 

Electronic Properties of Transition Metal Clusters Consideration of the Spillover in a Bulk Parametrization. 

This is the regime of cathodic currents. The silicon atoms of the electrode do not participate in the chemical reaction in this regime. An n-type electrode is under forward bias and the current is caused by majority carriers (electrons). The fact that photogenerated minority carriers (holes) are detectable at the collector indicates that the front is under flat band or accumulation. A decrease of IBC with cathodization time is observed. As Fig. 3.2 shows, the minority carrier current at the collector after switching to a cathodic potential is identical to that at VQcp in the first moment, but then it decreases within seconds to lower values, as indicated by arrows in Fig. 3.2. This can be interpreted as an increase of the surface recombination velocity with time under cathodic potential. It can be speculated that protons, which rapidly diffuse into the bulk of the electrode, are responsible for the change of the electronic properties of the surface layer [A17]. However, any other effect sufficient to produce a surface recombination velocity in excess of 100 cm s 1 would produce similar results. 

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