ISSN:
0009-2940
Schlagwort(e):
Diradicals
;
Gas-phase kinetics
;
Oxygen-trapping technique
;
Singlet-triplet splitting
;
Chemistry
;
Inorganic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Determination of the Singlet-Triplet Splitting of Diradicals by Oxygen-TrappingThe diradical 2, generated by thermolysis of 7-methylenebi-cyclo[3.2.0]hept-1-ene (1), can be trapped by oxygen in the gasphase. From the different trapping rates with and without added SF6 the intersystem crossing rates of the diradical have been deduced. From their temperature dependance the singlet-triplet splitting is calculated to be 7.4 kcal mol-1 with the triplet being the ground state. The triplet is protected by an enthalpy barrier of 13.0 kcal mol-1 against recombination of the unpaired electrons (2-tr→1). From the heat of hydrogenation of 1 the heat of formation of 1, 2-s and 2-tr is derived.
Zusätzliches Material:
2 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/cber.19911240928