Solvation and ionization stages of HCl on ice nanocrystals

2019-12-15 06:51:25

acid HCl ice adsorbate hydronium

责任者: Buch, V.;Sadlej, J.;Aytemiz-Uras, N.;Devlin, J.P. 单位: Fritz Haber Res. Center for Molecular Dynamics, Hebrew Univ., Jerusalem, Israel 来源出处: Journal of Physical Chemistry A(J. Phys. Chem. A (USA)),2002/10/17,106(41):9374-89 摘要: The study focuses on acid adsorption on cold ice particle surfaces. The investigation encompasses HCl, DCl, and HBr adsorbate spectroscopy, Monte Carlo simulations of molecular HCl adsorbate on a model ice particle, and ab initio studies of HCl solvation and ionization in mixed acid-water clusters.. It is shown that ice nanocrystal surfaces offer a range of adsorption sites, in which HCl freezes in different recognizable solvation stages. These stages were identified spectroscopically and assigned, with the help of calculations, to weakly and strongly stretched HCl molecules, and to Zundel and hydronium ions that are products of proton transfer. At moderate submonolayer coverages in the 50-60 K range, the acid adsorbate is predominantly molecular. Heating promotes formation of contact hydronium - chloride ion pairs. Near 90 K, an ionization burst is observed, resulting in an ionic surface hydrate layer rich in Zundel cations 关键词: adsorbed layers;deuterium compounds;digital simulation;hydrogen compounds;ice;ionisation;Monte Carlo methods;nanostructured materials;solvation;solvation;ionization stages;HCl;ice nanocrystals;acid adsorption;cold ice particle surfaces;DCl;HBr;adsorbate spectroscopy;Monte Carlo simulations;adsorbate;model ice particle;ab initio calculations;mixed acid-water clusters;ice nanocrystal surfaces;adsorption sites;freezing;weakly stretched HCl molecules;strongly stretched HCl molecules;Zundel ions;hydronium ions;proton transfer;submonolayer coverages;molecular acid adsorbate;contact hydronium - chloride ion pair formation