Hydration of Barium Monohydroxide in (H₂O)_1–3 Clusters: Theory and Experiment

Abstract

The ionization energies (IE e´s)Altogether, the present evidence suggests for the initial steps of the BaOH hydration process to be dominated by electrostatic and polarization interactions between the Ba + and OH -ion cores, which become both increasingly solvated upon sequential addition of water molecules.

Solvation of barium atoms and singly charged cations in acetonitrile clusters

“…The DFT approach was chosen on the basis of a previous study from this laboratory addressing to the photoionization of Ba(H 2 O) n clusters, 3 where in addition to mPW1PW91, three hybrid functionals had been evaluated, i.e., B3LYP, M06-2X, and the long range-corrected version of the functional wPBE, i.e, LC-wPBE, as defined in the Gaussian 09 package. As well, for Ba atoms, a number of pseudo-potentials (and their corresponding valence basis sets) were tried, such as SDD, CEP-121G, and LanL2DZ, as defined in the Gaussian 09 software and the RECP's developed by Lim et al, 22 and by Bauschlicher et al 23 25) added support for this theoretical approach to suitably describe systems, which are characterized by covalent and non-covalent interactions, including van der Waals interactions. 21 The successive binding energies (SBEs) for the solvation processes, Ba x (CH 3 CN) n−1 + CH 3 CN → Ba x (CH 3 CN) n , were estimated as…”

“…The BaNC + (or BaCN + ) and BaOH + species are presumably products of the reaction in the cluster source between Ba + ions and molecules of acetonitrile and with impurities (mainly water), respectively. 29 These species then become solvated in acetonitrile clusters, most likely by the evaporative process: 25 The lower panel of Fig. 1 shows the relative populations of the Ba + (CH 3 CN) n and BaNC + (CH 3 CN) n families as a function of n, as derived from the integrated intensities of the mass peaks corresponding to their dominant barium 138 isotopic components.…”

The role of orbiting resonances in the vibrational relaxation of I2(B,v′ = 21) by collisions with He at very low energies: a theoretical and experimental study

“…43 Interestingly, the positions of three of the orbiting resonances found nearly coincided with the energy positions of the cross section peaks observed experimentally. 30 Although the spectrum of vdW resonances in a triatomic complex typically changes slowly with increasing vibrational state v, the states v = 59 and 60 are rather far from the v = 21 state of I 2 (B)ÀHe probed experimentally. 30,31 It would be desirable to get a closer comparison between the theoretical and the experimental results, and this is the aim of the present work.…”

“…30 Although the spectrum of vdW resonances in a triatomic complex typically changes slowly with increasing vibrational state v, the states v = 59 and 60 are rather far from the v = 21 state of I 2 (B)ÀHe probed experimentally. 30,31 It would be desirable to get a closer comparison between the theoretical and the experimental results, and this is the aim of the present work. To that purpose, the I 2 (B,v 0 = 21) + He low energy collisions have been simulated by means of a wave packet method, and the cross sections corresponding to the collisional channels of interest have been calculated.…”

“…It is more recently that measured cross sections for I 2 (B,v 0 = 21) vibrational relaxation upon low temperature collisions with He that exhibit clear peaks at given collision energies have been reported for the first time. 30,31 The peaks of the cross section were attributed to orbiting resonances of the vdW I 2 (B,v 0 = 21) À He complex formed upon the low energy collisions. It is noted that (direct or indirect) evidence of the presence of orbiting resonances in vdW complexes has been found in spectroscopic experiments for the Br 2 -Ne, 32 ICl-He, 33 Br 2 -He, 34 and I 2 -He 35 complexes, and in time resolved experiments for the Br 2 -Ne complex.…”