Bond disruption energies

The oxidative addition reaction of I2 with (> -Cp )2Ln (Ln = Sm °" , Eu ° , Ybio.ii) j,ggj3 utilized as a thermodynamic anchor to determine absolute Ln-X bond disruption energies, D(Ln-X), in solution. Suitable thermodynamic cycles can be set up in which the ability to estimate an accurate value for >(Ln-I) is crucial to the accurate calculation of D(Ln-X) for various carbon- and silicon-donor ligands . Values for D(Ln-I) are obtained from reactions such as the one for Sm, where n (probably) equals 2 or 3 ° ... 

Likewise, U(III) complexes, such as [(f7 -Cp)2UCl]3 and U(2,4-C7Hn)3 have long been known to abstract halogen from I2, alkyl and aryl halides, and halogenated solvents . Reaction (e) was used as a thermodynamic anchor for the calculation of absolute U-X bond disruption energies ... 

Therefore, the BDE is also called the bond dissociation enthalpy. Here, species RX represent molecules, radicals, ions, and complexes, as well as clusters. The BDEs are commonly referred to as bond energies, bond strengths, binding energies, or bond disruption energies (enthalpies). The BE or D are other simplified abbreviation of the BDE in the literature. 

Systematic studies have been carried out to determine the a-bond disruption energies of lanthanide(III)-ligand a bonds in systems such as Cp 2Sm-R and Cp 2Sm-X (Cp denotes — (CH3)jC5 R denotes alkyl, H X denotes Cl, Br, I) (Nolan et al. 1989). 

Bond disruption energies for first and second Th-R bonds in [i7 -Me5C5ThR2], see reactions (71) and (72) and Section 11.2.13. 

The amount of radiation used is also important. A Nernst glower is used in ordinary infrared spectroscopy. This light source emits a relatively low amount of radiation, and no destruction of the analyzed material occurs. However, Raman infrared spectroscopy employs a radiation source of much greater energy. This radiation is sufficiently energetic to cause bond disruption and some destruction of the analyzed material. 

Given a method of preparing Mo organometallic compounds, the p decay transformation of Mo to Tc could be studied. The decay of Mo to Tc yields a nuclide with much lower recoil energy than that formed in the molybdenum (n, y ) process. However, this decay produces a cascade of Auger electrons see Auger Spectroscopy) which can cause bond disruption. These studies are difficult, because the technetium-99m product is produced at radiochemical tracer levels. Macroscopic quantities of products are not available for spectroscopic characterization. 

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