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Photoinduced bond breaking

It is also worth emphasizing that recent theoretical work on photoinduced stepwise and concerted electron transfer/bond-breaking reactions opens the route to a more systematic combination than before of the electrochemical and photochemical approaches to the same problems. [Pg.186]

In contrast to Fura-2, the photoinduced charge transfer in Indo-1 may not be sufficient to cause nitrogen-Ca2+ bond breaking. This interpretation is consistent with the fact that the fluorescence maximum of free Indo-1 is located at a shorter wavelength than Fura-2 by 30 nm, thus indicating a less polar charge-transfer state. [Pg.303]

Pincock and DeCosta [96] have recently described photoinduced bond cleavage reactions in a series of naphthylmethyl esters to produce both ionic and radical products. The authors attribute their results to excited state homolysis to form a caged radical pair and ET between the radicals to form an ion pair. The rates of ET have been rationalized by the Marcus theory which shows a Marcus inverted region where ET becomes slow when AG T is highly exothermic. In this case ET appears to follow homolytic bond cleavage rather than prior to bond breaking. [Pg.86]

By analogy with thermal processes (92), photoinduced isomerization s may occur either by intramolecular or intermolecular mechanisms. Intramolecular isomerizations are further classified either as "twisting" mechanisms, which involve no metal-ligand bond breaking, or as bond-rupture mechanisms. The latter term applies to reactions of chelate compounds in which one of the ligands is for a short time partially dissociated. Intermolecular mechanisms involve species other than those that make up the reactant complex. [Pg.243]

As already mentioned, most interesting are the properties of the aziridines connected with cleavage of the C-C bond of the sterically strained three-membered cycle, namely, thermo- and photoinduced cycloaddition reactions. Photo- and thermochromism inherent to these compounds are also linked with the breaking of this bond in the literature. [Pg.23]

In Chap. 3, wave packet propagation could be observed for nearly all of the alkali dimer and trimer systems considered, over a rather long time compared to the wave packet oscillation period. The wave packet dynamics - a fingerprint of the excited molecule - definitely characterize the excited bound electronic state of these molecules. However, with the results on K3 (excited with A 800 nm), another phenomenon, which often governs ultrafast molecular and cluster dynamics, comes into the discussion photodissociation induced by the absorption of single photons. This photoinduced dissociation permits detailed study of molecular dynamics such as breaking of bonds, internal energy transfer, and radiationless transitions. The availability of laser sources with pulses of a few tens of femtoseconds today opens a direct, i.e. real-time, view on this phenomenon. [Pg.131]


See other pages where Photoinduced bond breaking is mentioned: [Pg.137]    [Pg.137]    [Pg.165]    [Pg.247]    [Pg.268]    [Pg.125]    [Pg.709]    [Pg.55]    [Pg.3]    [Pg.315]    [Pg.264]    [Pg.60]    [Pg.246]    [Pg.378]    [Pg.230]    [Pg.182]    [Pg.81]    [Pg.215]    [Pg.154]    [Pg.307]    [Pg.209]    [Pg.416]    [Pg.1221]    [Pg.81]    [Pg.166]    [Pg.104]    [Pg.924]    [Pg.700]    [Pg.177]    [Pg.209]   
See also in sourсe #XX -- [ Pg.102 , Pg.137 ]




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Bond breaking

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