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arXiv · 0706.4217

W4 thermochemistry of P_2 and P_4. Is the CODATA heat of formation of phosphorus atom correct?

Amir Karton·Jan M. L. Martin
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Abstract

The high-accuracy W4 computational thermochemistry protocol, and several post-W4 methods, have been applied to the P$_2$ and P$_4$ molecules. Contrary to previous studies, we find the experimental thermochemistry to be fundamentally sound. The reaction enthalpy for P$_4\to 2$P$_2$ has a very significant contribution from post-CCSD(T) correlation effects. We derive a gas-phase heat of formation for the phosphorus atom of $ΔH^\circ_{f,0}$[P(g)]=75.54$\pm$0.1 kcal/mol and $ΔH^\circ_{f,298}$[P(g)]=75.74$\pm$0.1 kcal/mol, in the upper half of the CODATA uncertainty interval.

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Amir Karton, Jan M. L. Martin. 2007-06-28. W4 thermochemistry of P_2 and P_4. Is the CODATA heat of formation of phosphorus atom correct?. https://doi.org/10.1080/00268970701543572

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