Determination of the SmO+ bond energy by threshold photodissociation of the cryogenically cooled ion

2021 ◽  
Author(s):  
Anton Lachowicz ◽  
Evan H. Perez ◽  
Nicholas S. Shuman ◽  
Shaun Ard ◽  
Albert A. Viggiano ◽  
...  
Keyword(s):  
Bond Energy

A New Determination of the Fluoride Ion−Water Bond Energy

1999 ◽  
Vol 121 (14) ◽  
pp. 3531-3532 ◽  
Author(s):  
Patrick Weis ◽  
Paul R. Kemper ◽  
Michael T. Bowers ◽  
Sotiris S. Xantheas
Keyword(s):  
Bond Energy ◽  
Fluoride Ion

The C—Br bond dissociation energy in substituted benzyl bromides

1951 ◽  
Vol 209 (1096) ◽  
pp. 97-110 ◽  
Keyword(s):  
Bond Energy ◽  
Benzyl Bromide ◽  
Frequency Factor ◽  
Unimolecular Dissociation ◽  
Bond Dissociation Energies ◽  
Kcal Mole ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
Rate Determining Step

The ‘toluene-carrier’ technique has been used for the determination of the C—Br bond dissociation energies in the substituted benzyl bromides: p -, m - and o -xylyl bromides; p -, m - and o -chlorobenzyl bromides; p - and m -bromobenzyl bromides; p - and m -nitrobenzyl bromides; and p - and m -nitrilebenzyl bromides. The rate-determining step of the decompositions of all these compounds is represented by the unimolecular dissociation processes ( s ) Ph s . CH 2 . Br → Ph s . CH 2 • + Br, ( s ) where Ph s . CH 2 . Br refers to the substituted benzyl bromide. Assuming that the frequency factor of the decomposition of each benzyl bromide is equal to the frequency factor of reaction ( u ) Ph . CH 2 . Br → Ph . CH 2 • + Br, ( u ) the differences in activation energies between E u and E s were calculated using the relation E u ─ E s = RT In ( k s / k u ); (I) k s and k u denote the unimolecular rate constants of reactions ( s ) and ( u ) respectively. Since E s and E u are equal to the C—Br bond dissociation energies in the substituted benzyl bromides and benzyl bromide itself, equation (I) yields the differences, ∆ D’ s, between D ( Ph . CH 2 —Br) and the values for D ( Ph s . CH 2 —Br). The calculated differences in the C—Br bond dissociation energies are listed below: substituted ∆ D substituted ∆ D benzyl bromides (kcal. /mole) benzyl bromides (kcal. /mole) o -chloro 0·9 m -methyl 0-0 m -chloro 0·1 p -methyl 1·4 p -chloro 0·4 m -nitro 2·1 m -bromo 0·3 p -nitro 1·1 p -bromo 0·3 m -nitrile 1·4 o -methyl 2·0 p -nitrile 0·7 The significance of these findings is discussed, and the effect of substitution on a bond energy is contrasted with the effect of ionic reactions.

Theoretical Determination of the Co−C Bond Energy Dissociation in Cobalamins

2001 ◽  
Vol 123 (11) ◽  
pp. 2679-2680 ◽  
Author(s):  
Tadeusz Andruniow ◽  
Marek Z. Zgierski ◽  
Pawel M. Kozlowski
Keyword(s):  
Bond Energy ◽  
Theoretical Determination
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