Theoretical studies of the hydration of metaphosphate with one, two, and three molecules of water

Quantum mechanical calculations on phosphate hydrolysis reactions

“…The Δ S 0 value is overestimated at every level of theory, which is not surprising, as the calculated frequencies have not been scaled and the HF and B3LYP Δ H 0 lie slightly to either side of the experimental value. As expected, we obtained the same results obtained by Wu and Houk11 at the same level of theory. Ma et al also calculated the Δ H 0 of this reaction at the HF/DZP+diff, CISD/DZP+diff, and CCSD/DZP levels of theory, with values of 18.4, 16.5, and 12.9 kcal/mol, respectively, which are also in good agreement with our predictions.…”

“…A large difference is apparent between the HF level of theory and B3LYP/MP2 levels, while the data obtained with the latter two levels of theory are in good accordance with each other. We can compare this barrier with the highest level of theory employed by Wu and Houk11 MP4/6‐31+G**// HF/6‐31+G(*), which found a barrier of 33.10 kcal/mol for Rxn 3, a value between our HF and correlation methods. Blades et al21 determine this barrier energy experimentally from kinetic energy thresholds for the collision‐induced decomposition of [HOP(O 2 )OH] − .…”

“…In 1993, Wu and Houk11 and Ma et al12 studied the problem theoretically. By utilizing the transition state for Rxn 2b proposed by Wu and Houk, we study the dephosphorylation of the phosphorylated hydroxyl aminoacids (serine, threonine, and tyrosine).…”

Large amplitude motion in cold monohydrated dihydrogen phosphate anions H2PO4−(H2O): infrared photodissociation spectroscopy combined with ab initio molecular dynamics simulations

“…Early studies on the PO 3 À + H 2 O reaction in the gas phase 4 found that metaphosphate is unreactive, even though H 2 PO 4 À is thermodynamically more stable, owing to a high activation barrier. High pressure mass spectroscopic investigations by Keesee and Castleman, 5 supported by electronic structure calculations, 6,7 suggested that formation of dihydrogen phosphate does occur in the third hydration step and that PO 3 water in a double donor (DD) configuration bound to the two unprotonated phosphoryl O-atoms. 7,[11][12][13] An alternative arrangement with the water in an acceptor-donor (AD) motif is found to be higher in energy.…”

“…High pressure mass spectroscopic investigations by Keesee and Castleman, 5 supported by electronic structure calculations, 6,7 suggested that formation of dihydrogen phosphate does occur in the third hydration step and that PO 3 water in a double donor (DD) configuration bound to the two unprotonated phosphoryl O-atoms. 7,[11][12][13] An alternative arrangement with the water in an acceptor-donor (AD) motif is found to be higher in energy. 11 However, no experimental gas-phase data regarding the cluster structures are available.…”