%0 Journal Article
%A Wheeler, Oscar
W.
%A Carl, Damon R.
%A Hofstetter, Theresa
E.
%A Armentrout, P. B.
%D 2015
%T Hydration Enthalpies of Ba2+(H2O)x, x = 1–8:
A Threshold Collision-Induced Dissociation and Computational Investigation
%U https://acs.figshare.com/articles/journal_contribution/Hydration_Enthalpies_of_Ba_sup_2_sup_H_sub_2_sub_O_sub_i_x_i_sub_i_x_i_1_8_A_Threshold_Collision_Induced_Dissociation_and_Computational_Investigation/2173810
%R 10.1021/acs.jpca.5b01087.s001
%2 https://acs.figshare.com/ndownloader/files/3807736
%K electrospray ionization source
%K B 3LYP calculations
%K H 5O Modeling
%K Ba
%K Hydration
%K Computational InvestigationThe sequential bond dissociation energies
%K MP
%K charge separation
%K 0 K BDEs
%K TCID
%K ion beam tandem mass spectrometer
%K complex
%X The sequential bond dissociation
energies (BDEs) of Ba2+(H2O)x complexes, where x = 1–8, are determined
using threshold collision-induced
dissociation (TCID) in a guided ion beam tandem mass spectrometer.
The electrospray ionization source generates complexes ranging in
size from x = 6 to x = 8 with smaller
complexes, x = 1–5, formed by an in-source
fragmentation technique. The only products observed result from sequential
loss of water ligands. Charge separation, a process in which both
hydrated singly charged barium hydroxide and hydronium ion are formed,
was not observed except for Ba2+(H2O)3 yielding BaOH+ + H5O2+. Modeling of the kinetic energy-dependent cross sections, taking
into account the number of collisions, energy distributions, and lifetime
effects for both primary and secondary water loss, provides 0 K BDEs.
Experimental thermochemistry for the x = 1–3
complexes is obtained here for the first time. Hydration enthalpies
and reaction coordinate pathways for charge separation are also examined
computationally at several levels of theory. Our experimental and
computational work are in excellent agreement in the x = 1–6 range. The present experimental values and theoretical
calculations are also in reasonable agreement with the available literature
values for experiment, x = 4–8, and theory, x = 1–6. Of the numerous calculations performed in
the current study, B3LYP/DHF/def2-TZVPP calculations including counterpoise
corrections reproduce our experimental values the best, although MP2(full)/DHF/def2-TZVPP//B3LYP/DHF/def2-TZVPP
results are comparable.
%I ACS Publications