Molecular orbital analysis abstraction

Abstract The agostic bond defines an intramolecular interaction where a a bond is geometrically close to an electron deficient centre (often a transition metal). The computational studies on this energetically weak interaction are reviewed and discussed. Various types of a bonds have been considered (C-H, C-C, Si-H, Si-C, B-H). It is suggested that a C-X bond in which X carries a lone pair should preferably not be viewed as agostic. The factors that contribute to his occurrence are discussed. In particular, the agostic interaction is very sensitive to steric effects. Explanations based on molecular orbital analysis, electron delocalization and topological analysis of the electron density are presented. 

The iodide-abstraction reaction of [ Rh(/i-I)(/i-RNNNR)2(CO)(bipy) 2][PF6]2 (bipy = 2,2 -bipyridyl, R=/)-tolyl) with AgPFe in MeCN gave [Rh2(CO)(NCMe)2(bipy)(/r-RNNNR)2][PF6]2 which slowly decarbonylated at room temperature to [Rh2(NCMe)3(bipy)(/r-RNNNR)2][PF6]2." " The molecular structures of a series of dirhodium carbonyl complexes with local planar symmetry about each rhodium atom were extensively studied. Different bridging N-N IS and N-0 16 ligands support the dimetallic structures." Many such complexes are long known,but a complete molecular orbital analysis has been described. 

Abstract A molecular orbital analysis of model unbridged complexes with Cr-Cr formal bond orders four and five is presented, based on density functional calculations. The orbital and symmetry analysis discloses a special type of 8 bmiding in the case of the [Ct2L4] complexes that induces a significant bond shortening going from quadruple Cr°-Cr to quintuple Cr -Cr bonds. 

Abstract. The subject paper presented the first conformational analysis of the anomeric effect within the context of molecular orbital theory, discussed the utility of Fourier decomposition of a torsional coordinate as a method for analyzing disparate electronic influences on that coordinate, and helped settle debate on the nature of anomeric stabilization. 

Abstract This work reports the formulation of Shannon entropy indices in terms of seniority numbers of the Slater determinants expanding an A-electron wave fimc-tion. Numerical determinations of those indices prove that they provide a suitable quantitative procedure to evaluate compactness of wave functions and to describe their configurational structures. An analysis of the results, calculated for full configuration interaction wave functions in selected atomic and molecular systems, allows one to compare and to discuss the behavior of several types of molecular orbital basis sets in order to achieve more compact wave... 

Abstract. The development of modern spectroscopic techniques and efficient computational methods have allowed a detailed investigation of highly excited vibrational states of small polyatomic molecules. As excitation energy increases, molecular motion becomes chaotic and nonlinear techniques can be applied to their analysis. The corresponding spectra get also complicated, but some interesting low resolution features can be understood simply in terms of classical periodic motions. In this chapter we describe some techniques to systematically construct quantum wave functions localized on specific periodic orbits, and analyze their main characteristics. 

ABSTRACT. The study of periodic orbits embedded in the continuum has provided a new tool for understanding the dynamics of molecular collisions, The application of periodic orbit theory to classical variational transition state theory, quantal threshold and resonance effects is presented. Special emphasis is given to the stability analysis of periodic orbits in collinear and three dimensional systems. Future applications of periodic orbit theory are outlined. 

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