Singlet-triplet energy gaps in fluorine-substituted methylenes and silylenes
نویسندگان
چکیده
We report singlet and triplet state splittings (I:J.EsT) for fluorine-substituted methylenes and silylenes using dissociation-consistent configuration interaction (CI) (based on generalized valence bond wave functions). These relatively simple CI calculations emphasize correlation consistency between the singlet and triplet states. Values of I:J.Esr for CH2, CF2, SiH2, and SiF2 are in excellent agreement with available experimental results, and we expect the predictions for the other cases CHF (14.5) and SiHF ( 41.3) to be equally accurate. This result strongly suggests that the correct choice among the experimental values for I:J.Esr of CHF is 14.7 ±0.2 kcal/mol.
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