ACCURATE D-0 VALUES FOR SIF AND SIF+

Highly accurate D-0 values are determined for SiF and SiF+ using the C CSD(T) approach in conjunction with basis set extrapolation. The resul ts include the effect of spin-orbit coupling and core-valence correlat ion. Our best D-0, estimates for SiF and SiF+ are 141.5 and 159.7 kcal /mol, respectively, which we estimate to have an uncertainty of +/-1.0 kcal/mol. For SIF, the value is significantly larger than the older e xperiments and only slightly larger than the most recent experiment. O ur value is slightly larger than previous calculations. For SiF+ our b est estimate is in good agreement with previous calculations and sligh tly smaller than the experimental value. (C) 1998 Elsevier Science B.V . All rights reserved.