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Electronic structure review

Ortiz J V 1997 The electron propagator picture of molecular electronic structure Computational Chemistry Reviews of Current Trends vo 2, ed J Leszczynski (Singapore World Scientific) pp 1-61... [Pg.2200]

GAMESS stands for general atomic and molecular electronic structure system (we reviewed a version dated Dec. 2, 1998). It is an ah initio and semiempirical program, and has seen the most widespread use for ah initio calculations. The ASCII input hie format is usable but somewhat more lengthy than some other programs. The fact that GAMESS is a free, high-quality software makes it a favorite of many academic researchers. [Pg.335]

The first empirical and qualitative approach to the electronic structure of thiazole appeared in 1931 in a paper entitled Aspects of the chemistry of the thiazole group (115). In this historical review. Hunter showed the technical importance of the group, especially of the benzothiazole derivatives, and correlated the observed reactivity with the mobility of the electronic system. In 1943, Jensen et al. (116) explained the low value observed for the dipole moment of thiazole (1.64D in benzene) by the small contribution of the polar-limiting structures and thus by an essentially dienic character of the v system of thiazole. The first theoretical calculation of the electronic structure of thiazole. benzothiazole, and their methyl derivatives was performed by Pullman and Metzger using the Huckel method (5, 6, 8). [Pg.26]

In this chapter, we have reviewed the RISM-SCF/MCSCF method, which combines electronic structure and liquid-state theories to deal with the chemistry of solutions. The ability... [Pg.436]

Abstract—The fundamental relations governing the geometry of carbon nanotubes are reviewed, and explicit examples are pre.sented. A framework is given for the symmetry properties of carbon nanotubes for both symmorphic and non-symmorphic tubules which have screw-axis symmetry. The implications of symmetry on the vibrational and electronic structure of ID carbon nanotube systems are considered. The corresponding properties of double-wall nanotubes and arrays of nanotubes are also discussed. [Pg.27]

Electronic structures of SWCNT have been reviewed. It has been shown that armchair-structural tubes (a, a) could probably remain metallic after energetical stabilisation in connection with the metal-insulator transition but that zigzag (3a, 0) and helical-structural tubes (a, b) would change into semiconductive even if the condition 2a + b = 3N s satisfied. There would not be so much difference in the electronic structures between MWCNT and SWCNT and these can be regarded electronically similar at least in the zeroth order approximation. Doping to CNT with either Lewis acid or base would newly cause intriguing electronic properties including superconductivity. [Pg.48]

This review demonstrates that representatives of all four major classes of heterocyclic mesomeric betaines were isolated from natural sources. The profound differences in the electronic structures of these distinct classes can be realized by a closer look at the canonical formulae, the frontier orbital profile, the isoconjugate relationships, physico-organic properties, and the... [Pg.73]

As is well recognized, various macroscopic properties such as mechanical properties are controlled by microstructure, and the stability of a phase which consists of each microstructure is essentially the subject of electronic structure calculation and statistical mechanics of atomic configuration. The main subject focused in this article is configurational thermodynamics and kinetics in the atomic level, but we start with a brief review of the stability of microstructure, which also poses the configurational problem in the different hierarchy of scale. [Pg.83]

Freed, K. F. [1971] Many-Body Theories of the Electronic Structure of Atoms and Molecules , Annual Review of Physical Chemistry, 22, p. 313. [Pg.32]

This review aims to present an account of the catalytic properties of palladium and nickel hydrides as compared with the metals themselves (or their a-phase solid solutions with hydrogen). The palladium or nickel alloys with the group lb metals, known to form /8-phase hydrides, will be included. Any attempts at commenting on the conclusions derived from experimental work by invoking the electronic structure of the systems studied will of necessity be limited by our as yet inadequate knowledge concerning the electronic structure of the singular alloys, which the hydrides undoubtedly are. [Pg.246]

The screened proton model of nickel or palladium hydrides and Switendick s concept of the electronic structure do not constitute a single approach sufficient to explain the observed facts. In this review, however, such a model will be used as the basis for further discussions. It allows for the explanation and general interpretation of the observed change of catalytic activity of the metals, when transformed into their respective hydrides. [Pg.251]

The fundamental understanding of the diazonio group in arenediazonium salts, and of its reactivity, electronic structure, and influence on the reactivity of other substituents attached to the arenediazonium system depends mainly on the application of quantitative structure-reactivity relationships to kinetic and equilibrium measurements. These were made with a series of 3- and 4-substituted benzenediazonium salts on the basis of the Hammett equation (Scheme 7-1). We need to discuss the mechanism of addition of a nucleophile to the P-nitrogen atom of an arenediazonium ion, and to answer the question, raised several times in Chapters 5 and 6, why the ratio of (Z)- to ( -additions is so different — from almost 100 1 to 1 100 — depending on the type of nucleophile involved and on the reaction conditions. However, before we do that in Section 7.4, it is necessary to give a short general review of the Hammett equation and to discuss the substituent constants of the diazonio group. [Pg.148]

Benzocyclopropene is an intriguing example in which the electronic structure of benzene is greatly perturbed by the fusion of the smallest alicyclic ring, cyclopropene, to the aromatic system. Benzocyclopropene thus arouses theoretical interest and the high strain energy (approximately 68 kcal./mole)3 associated with the compound suggests unusual chemical reactivity. A review article has recently appeared.4... [Pg.14]

Metal complexes of 1,1-dithiolates have been reviewed by Coucou-vanis (1) Eisenberg (2) presented a systematic, structural review of dithiolato chelates, and Stokolosa ct al. (3) reviewed dithiophosphate complexes in detail. Earlier reviews (4-3) covered less recent work in greater detail. Following initial work by Delepine (9), 1,1-dithiolato complexes were more intensively studied between 1930 and 1941 (10-16). There is, however, continuous interest in the synthesis, characterization, electronic structures, and bonding of these complexes. [Pg.212]

Some typical reactions in the pseudoexcitation band are reviewed in this section. The importance of pseudoexcitation [1] in chemical reactions was supported by the detailed numerical analysis of the electronic structures of the transion states [66]. The concept of pseudoexcitation appeared in physics [67-69]. [Pg.37]

The different classes of Ru-based catalysts, including crystalline Chevrel-phase chalcogenides, nanostructured Ru, and Ru-Se clusters, and also Ru-N chelate compounds (RuNj), have been reviewed recently by Lee and Popov [29] in terms of the activity and selectivity toward the four-electron oxygen reduction to water. The conclusion was drawn that selenium is a critical element controlling the catalytic properties of Ru clusters as it directly modifies the electronic structure of the catalytic reaction center and increases the resistance to electrochemical oxidation of interfacial Ru atoms in acidic environments. [Pg.316]

Hess, B.A. (1986) Relativistic electronic-structure calculations employing a two-component no-pair formalism with external-field projection operators. Physical Review A, 33, 3742-3748. [Pg.226]

Hakkinen, H., Moseler, M., Kostko, O., Morgner, N., Hoffmann, M.A. and Issendorff, B. v. (2004) Symmetry and Electronic Structure of Noble-Metal Nanopartides and the Role of Relativity. Physical Review Letters, 93, 093401-1-093401-4. [Pg.240]

Loucks, T.L. (1966) Relativistic Electronic Structure in Crystals. II. Eermi Surface of Tungsten. Physical Review, 143, 506-512. [Pg.242]

Theileis, V. and Bross, H. (2000) Relativistic modified augmented plane wave method and its application to the electronic structure of gold and platinum. Physical Review B - Condensed Matter, 62, 13338-13346. [Pg.242]

Yang, X. and Dong, J. (2005) Geometrical and electronic structures of the (5, 3) single-walled gold nanotube from first-principles calculations. Physical Review B -Condensed Matter, 71,233403-1-233403-4. [Pg.246]

In Section 2 the general features of the electronic structure of supported metal nanoparticles are reviewed from both experimental and theoretical point of view. Section 3 gives an introduction to sample preparation. In Section 4 the size-dependent electronic properties of silver nanoparticles are presented as an illustrative example, while in Section 5 correlation is sought between the electronic structure and the catalytic properties of gold nanoparticles, with special emphasis on substrate-related issues. [Pg.78]

In this chapter, we will focus on some of the recent developments in understanding the influence of solution and electrochemical conditions over model single-crystal surfaces. Specifically, we will review work applying electronic structure methods to probe electrocatalytic mechanisms occurring at this complex interface. [Pg.94]


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