4 J ul 1 99 9 The heat of atomization of sulfur trioxide , SO 3 — a benchmark for computational thermochemistry Jan
نویسنده
چکیده
Calibration ab initio (direct coupled cluster) calculations including basis set extrapolation, relativistic effects, inner-shell correlation, and an anharmonic zero-point energy, predict the total atomization energy at 0 K of SO 3 to be 335.96 (observed 335.92±0.19) kcal/mol. Inner polarization functions make very large (40 kcal/mol with spd, 10 kcal/mol with spdf g basis sets) contributions to the SCF part of the binding energy. The molecule presents an unusual hurdle for less computationally intensive theoretical thermochemistry methods and is proposed as a benchmark for them. A slight modification of Weizmann-1 (W1) theory is proposed that appears to significantly improve performance for second-row compounds.
منابع مشابه
The heat of atomization of sulfur trioxide, SO3 — a benchmark for computational thermochemistry
Calibration ab initio (direct coupled cluster) calculations including basis set extrapolation, relativistic effects, inner-shell correlation, and an anharmonic zero-point energy, predict the total atomization energy at 0 K of SO3 to be 335.96 (observed 335.92±0.19) kcal/mol. Inner polarization functions make very large (40 kcal/mol with spd, 10 kcal/mol with spdfg basis sets) contributions to t...
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