Threshold Collision-Induced Dissociation of Hydrated Thorium(IV) Trihydroxide Cation: Experimental and Theoretical Investigation of the Binding Energies for Th(OH)3+(H2O)n Complexes (n = 1–4)

Kafle, Arjun; Nwokolo, Chinye; Sanchez, Lauren; Armentrout, P. B.

doi:10.1021/acs.jpca.9b11516

Title: Threshold Collision-Induced Dissociation of Hydrated Thorium(IV) Trihydroxide Cation: Experimental and Theoretical Investigation of the Binding Energies for Th(OH)₃⁺(H₂O)_n Complexes (n = 1–4)

Journal Article · Mon Mar 30 00:00:00 EDT 2020 · Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory

DOI:https://doi.org/10.1021/acs.jpca.9b11516· OSTI ID:1615742

^[1]; Nwokolo, Chinye ^[2]; Sanchez, Lauren ^[3];

^[1]

Univ. of Utah, Salt Lake City, UT (United States)
Univ. of Utah, Salt Lake City, UT (United States); Palm Research Center, Inc, Las Vegas, NV (United States)
Univ. of Utah, Salt Lake City, UT (United States); Oxnard College, CA (United States)

Threshold collision-induced dissociation of Th(OH)₃⁺(H₂O)_n Complexes (n = 1–4) with xenon was performed using a guided ion beam tandem mass spectrometer. The primary dissociation pathway for all complexes is a loss of a single water molecule followed by the sequential loss of additional water molecules at higher collision energies. Here, the data were analyzed using a statistical model after accounting for lifetime effects and reactant internal and kinetic energy distributions to obtain 0 K bond dissociation energies (BDEs). These were also converted using rigid rotor/harmonic oscillator approximations to yield thermodynamic values at room temperature. The 0 K BDEs of H₂O ligands to Th(OH)₃⁺ (IV) are experimentally determined for the first time as 106 ± 6, 89 ± 6, 76 ± 4, and 51 ± 4 kJ/mol for the first, second, third, and fourth water ligand added. These values agree reasonably well with values calculated at the B3LYP, B3PW91, and PBE0 levels of theory with aug-cc-pVQZ basis sets, whereas B3LYP-GD3BJ, MP2, and CCSD(T) single point energies with (without) counterpoise corrections systematically overestimate the bond energies by about 15 (20), 19 (25), and (18) kJ/mol, respectively.

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Research Organization:: Univ. of Utah, Salt Lake City, UT (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

Grant/Contract Number:: SC0012249

OSTI ID:: 1615742

Journal Information:: Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, Vol. 124, Issue 16; ISSN 1089-5639

Publisher:: American Chemical SocietyCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 7 works

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Title: Threshold Collision-Induced Dissociation of Hydrated Thorium(IV) Trihydroxide Cation: Experimental and Theoretical Investigation of the Binding Energies for Th(OH)₃⁺(H₂O)_n Complexes (n = 1–4)