Bonding energetics

In the end, mass spectrometry and ion techniques will continue to be powerful tools for the investigation of the structure, bonding, energetics, and reactivity of unusual organic molecules. New sophisticated techniques will continue to be developed and applied to interesting problems in physical organic chemistry. These studies, along with the continued improvements in computational methods (Chapter 9), provide means to obtain very detailed and accurate descriptions of chemical reactions. 

Apparently, there is not much advantage in using bond enthalpy contributions to discuss bonding energetics in a series of similar complexes. As already stated, we could have selected any value for Z)//,°(Cr-CO) + DH (Cr-CO) + Z)//j (Cr-CO) and then derived chromium-arene bond dissociation enthalpies in Cr(CO)3(arene) compounds, all based on the same anchor. The trend would not be affected by our choice. Nevertheless, besides emphasizing that the absolute values so obtained should not be regarded as bond dissociation enthalpies, the bond enthalpy contribution concept attempts to consider a pertinent issue in molecular energetics the transferability of bond enthalpies. 

Bonding Energetics in Organometallic Compounds Marks, T. J. Ed. ACS Symp. Ser. 428 American Chemical Society Washington, D. C., 1990 pp. 1-305... 

Bond energetics and rehybridization from spin-uncoupling... 

A. R. Dias, H. P. Diogo, D. Griller, M. E. Pinas de Piedade and J. A. Martinho Si mix s, Bonding Energetics in Organometallic Compounds, ACS Symposium Series No. 428 (Ed. T. Marks), Chap. 14 (Metal Bond Dissociation Enthalpies from Classical and Nonclassical Calorimetric Studies), 1990, p. 205. 

In any catalytic process, several of these mechanisms can operate in concert, and they may be augmented by additional effects such as hydrogen bond energetics (7-9), turmeling (10), and bonding of substrates to transition metal centers. In many cases, the mechanisms are interdependent, and the line of demarcation between one and another is not obvious. 

During the last 10 years, significant advances have been made in the area of organometallic bonding energetics. Most data were obtained from solution calorimetric studies. In the present chapter, a compilation of thermochemical data on organometallic systems is presented. This account represents a survey and is by no means exhaustive yet we have endeavored to provide the reader with as much data as possible in an effort to complement the contribution found in the first edition. 

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