Bond dissociation energies of C-H bonds in several haloethylenes, as estimated from the recoil tritium abstraction reaction
The abstraction yields from the reaction T + RH ..-->.. HT + R have been measured for a series of haloethylenes under standard conditions in an excess of C/sub 2/D/sub 4/. The tritium atoms have been produced with excess energy from the nuclear reaction /sup 3/He(n,p)T. The order of decreasing HT yield per C-H bond is cis-CHCl=CHCl > cis-CFCl=CHCl > CH/sub 2/ = CH/sub 2/ approx. = CF/sub 2/=CHCl > cis-CHF=CHF approx. = CF/sub 2/=CH/sub 2/ > CF/sub 2/=CHF. The C-H bond dissociation energies of these compounds can be estimated from these yields and range relative to C-H in C/sub 2/H/sub 4/ from -2 kcal/mol, for cis-CHCl=CHCl to +2 kcal/mol for CF/sub 2/=CHF. With the current value of 109 +- 1 kcal/mol for the bond dissociation energy of ethylene, these values for the halothylenes fall in the range from 107 to 111 kcal/mol.
- Research Organization:
- Univ. of California, Irvine
- DOE Contract Number:
- AT03-76ER70126
- OSTI ID:
- 6934548
- Journal Information:
- J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Journal Issue: 2 Vol. 85:2; ISSN JPCHA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Bond strengths of ethylene and acetylene
Heterogeneous hydrogenolysis of some fluorocarbons
Related Subjects
400701* -- Radiochemistry & Nuclear Chemistry-- Hot-Atom Chemistry
ALKENES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHEMISTRY
CHLORINATED ALIPHATIC HYDROCARBONS
ETHYLENE
FLUORINATED ALIPHATIC HYDROCARBONS
HALOGENATED ALIPHATIC HYDROCARBONS
HOT ATOM CHEMISTRY
HYDROCARBONS
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
NUCLEI
ODD-EVEN NUCLEI
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
RADIOCHEMISTRY
RADIOISOTOPES
RECOILS
TRITIUM
YEARS LIVING RADIOISOTOPES