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Updated: Jul 7, 2026
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Combined quantum mechanical and molecular mechanics studies of the electron-transfer reactions involving carbon
Marat Valiev1, Eric J Bylaska, Michel Dupuis
1William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Abstract:
The reductive dechlorination of carbon tetrachloride, CCl4, by a concerted electron transfer-bond breaking mechanism was studied using combined high level quantum mechanical and molecular mechanics (QM/MM) approach. The free energy activation barriers for the first electron-transfer step were determined from the dissociation profiles of CCl4 and *CCl4(-) complexes in aqueous phase using hybrid-free energy QM/MM methodologies. Both density functional and coupled cluster perturbative triples (CCSD(T)) versions of QM/MM methods were investigated. The impact of the implicit solvent description based on continuum (COSMO) solvent models was also analyzed. QM/MM calculations at the CCSD(T)/aug-cc-pVDZ/SPCE level of theory predict that the activation barriers vary from 0.7 to 35.2 kcal/mol for -2.32 and 0.93 V reduction potentials respectively. Good agreement with experimental data for oxide-free iron electrodes (-0.6 to -1.2 V reduction potentials) is observed indicating that the measured activation barriers are consistent with the concerted electron transfer-bond-breaking mechanism.
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