2007
Why Urea Eliminates Ammonia Rather than Hydrolyzes in Aqueous Solution
Alexandrova AN, Jorgensen WL. Why Urea Eliminates Ammonia Rather than Hydrolyzes in Aqueous Solution. The Journal Of Physical Chemistry B 2007, 111: 720-730. PMID: 17249815, PMCID: PMC2995377, DOI: 10.1021/jp066478s.Peer-Reviewed Original ResearchConceptsAddition/elimination mechanismDecomposition of ureaWater moleculesResonance stabilizationAqueous solutionNH3 eliminationNatural bond order analysisQM/MM Monte Carlo simulationsBond order analysisFree energy perturbation calculationsQM/MMExplicit water modelRate-determining stepElimination mechanismOverall free energyLow activation energySolvent effectsElimination reactionHydrogen bondsPreferred reaction routeReaction routeGas phaseTransition stateZwitterionic intermediateAb initio
2006
Elucidation of Rate Variations for a Diels−Alder Reaction in Ionic Liquids from QM/MM Simulations
Acevedo O, Jorgensen WL, Evanseck JD. Elucidation of Rate Variations for a Diels−Alder Reaction in Ionic Liquids from QM/MM Simulations. Journal Of Chemical Theory And Computation 2006, 3: 132-138. PMID: 26627159, DOI: 10.1021/ct6002753.Peer-Reviewed Original ResearchQM/MM simulationsIonic liquidsEMI cationTransition stateMM simulationsOPLS-AA force field parametersQM/MM calculationsBasic ionic liquidFree energy perturbation calculationsReaction rateHydrogen bond donorForce field parametersLewis acid effectRelative rate enhancementKey stationary pointsSolute-solvent interactionsEndo/exo ratioAcidic meltsBond donorHydrogen bondingMM calculationsWater moleculesAqueous solutionHydrogen bondsElectrostatic interactions