Reactions endoergic

The further course of reaction is determined by the angle 0i. Any trajectory 

A barrier in the product channel (Fig. 10.12c) can only be surmounted if El — E cos 6 A. In this example the endoergicity is due to attraction between C and the center of mass of AB. Here a small amount of vibrational energy is far more effective in promoting reaction than is increasing the translational energy. As long s — n/2 6 ip — njl, (10.13) or (10.14) are valid for all p and 

As usual El depends on the sign of 0. If /5 w/3, / is larger for 0 positive. Using (10.11) and choosing the phase which maximizes /, (10.20) becomes 

If the initial total energy is E it is completely available for surmounting the barrier only if 

unless = 60°, a small amount of vibrational energy is required in order to most efficiently utilize the available translational energy. The effect is clearly demonstrated in the reaction  

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The previous treatment applies to exoergic chemical reactions (with positive energy difference between the minima of the initial and final states AE = — > 0)- For endoergic reactions... 

Endoergic Reactions (Electronically and Vibrationally Excited States)... 

Other endoergic reactions for which an increased cross section has been observed when the internal vibrational energy of the ionic reactant... 

If A < 0 (endoergic or endoenergetic reactions), the missing energy must be introduced by the projectile x. By application of the law of conservation of momentum, the minimum energy of the projectiles for endoergic reactions is calculated to be... 

The general term for a reaction that takes in energy is endoergic. Chlorophyll is involved in a very important endoergic reaction. What is the reaction and what are the reagents and products ... 

We have applied DPA to tert-butyl and iec-butyl chlorides. As discussed in other sections, the difference in stabilities we obtained was in excellent agreement with that provided by other methods. The most important point, however, is that the DPA onset for iec-BuCl could be clearly determined, in spite of the fact that iec-Bu readily rearranges to tert-Bu. This is explained by the fact that the DPA are entropy-driven, endoergic reactions. This makes DPA extremely valuable for the study of relatively unstable species. Examples of such processes are known. They are currently under study in our laboratories. 

This increase in mass corresponds to a Q-value of — 1.19 MeV (12.2). The energy required for this endoergic reaction can only be obtained through the kinetic energy of the projectile. 

MeV for it to overcome the coulomb barrier. For the above reaction to take place with high probability, the incident neutron must have a minimum kinetic energy of 1.9 + 2.9 = 4.8 MeV. Endoergic reactions are also called threshold reactions. 

Carbon Dioxide. The endoergic reaction (82) is promoted by sufficiently energetic... 

Endoergic Reactions Determination of Heats of Formation from Thresholds... 

The distribution between vibrational and/or electronic states of the products is discussed. The effect of vibrational and/or electronic excitation of the reactants is discussed. Endoergic reaction, exhibiting a threshold. 

Maxwellian distribution) and excitation functions. The paper considers the application of the approach to endoergic reactions, in particular 0 (02,0)02". The actual kinetic data—k as a function of E/p—is well simulated by the model if a drastically simplified form is assumed for the excitation function (see Chapter 4, Fig. 5 for the various versions of the experimental excitation function). This result and others in the paper indicate that the kinetic data are rather insensitive to the form assumed for the excitation function, confirming again the extreme difficulty of unfolding excitation functions from rate-constant data (Section 2.1). 

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