<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Baltrusaitis, Jonas</style></author><author><style face="normal" font="default" size="100%">Schuttlefield, Jennifer</style></author><author><style face="normal" font="default" size="100%">Jensen, Jan H.</style></author><author><style face="normal" font="default" size="100%">Grassian, Vicki H.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">FTIR spectroscopy combined with quantum chemical calculations to investigate adsorbed nitrate on aluminum oxide surfaces in the presence and absence of co-adsorbed water.</style></title><secondary-title><style face="normal" font="default" size="100%">Physical Chemistry Chemical Physics</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">adsorption surface reaction nitrate alumina water coadsorption</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007///</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">Royal Society of Chemistry</style></publisher><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">4970 - 4980</style></pages><isbn><style face="normal" font="default" size="100%">1463-9076</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Surface reactions of nitrogen oxides with aluminum oxide particles result in the formation of adsorbed nitrate.  Specifically, when α-Al2O3 and γ-Al2O3 particles are exposed to gas-phase NO2 and HNO3 adsorbed nitrate forms on the surface.  In this study, Fourier transform IR (FTIR) spectroscopy is combined with quantum chem. calcns. to further our understanding of the adsorbed nitrate product on aluminum oxide particle surfaces in the presence and absence of co-adsorbed water at 296 K.  FTIR spectra of adsorbed nitrate on α-Al2O3 and γ-Al2O3 particles are interpreted using calcd. vibrational frequencies of nitrate coordinated to binuclear Al oxide cluster models.  Comparison of the calcd. and exptl. vibrational frequencies of adsorbed nitrate establishes different modes of coordination (monodentate, bidentate and bridging) of the nitrate ion to the surface in the absence of adsorbed water.  In the presence of co-adsorbed water, the nitrate ion becomes fully solvated, as shown by a comparison of the exptl. nitrate IR spectra as a function of relative humidity with the calcd. nitrate vibrational frequencies for binuclear Al cluster compds. which contain both coordinated nitrate ions and water mols.  These calcns. also suggest that adsorbed water can displace nitrate from direct coordination to the surface, leading to an outer-sphere nitrate adsorption complex as well as an inner-sphere complex.  Furthermore, the relative humidity dependence of the spectra suggest that water does not evenly wet the surface even at high relative humidity, as there are open or bare surface sites where nitrate ions are not solvated.  Besides adsorbed monodendate, bidendate, bridging and solvated nitrate, the presence of ion bound nitrate ion, partially solvated nitrate, mol. nitric acid, hydronium ion and H3O+:NO3- ion pairs on the oxide surface are also discussed. [on SciFinder(R)]</style></abstract><issue><style face="normal" font="default" size="100%">36</style></issue><notes><style face="normal" font="default" size="100%">CAPLUS AN 2007:1019734(Journal)</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Baltrusaitis, Jonas</style></author><author><style face="normal" font="default" size="100%">Jensen, Jan H.</style></author><author><style face="normal" font="default" size="100%">Grassian, Vicki H.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">FTIR Spectroscopy Combined with Isotope Labeling and Quantum Chemical Calculations to Investigate Adsorbed Bicarbonate Formation Following Reaction of Carbon Dioxide with Surface Hydroxyl Groups on Fe2O3 and Al2O3.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Physical Chemistry B</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">adsorption carbon dioxide hydroxylated metal oxide surface chemisorption</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006///</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">American Chemical Society</style></publisher><volume><style face="normal" font="default" size="100%">110</style></volume><pages><style face="normal" font="default" size="100%">12005 - 12016</style></pages><isbn><style face="normal" font="default" size="100%">1520-6106</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">FTIR spectroscopy combined with isotope labeling expts. and quantum chem. calcns. is used to investigate the adsorption of carbon dioxide on hydroxylated metal oxide surfaces.  In particular, transmission FTIR spectra following CO2 adsorption on hydroxylated nanoparticulate Fe2O3, α-Al2O3, and γ-Al2O3 particles at 296 K are reported.  As expected, reaction of CO2 with these surfaces results in the formation of adsorbed bicarbonate and carbonate.  In this study, the vibrational spectrum of the bicarbonate product is analyzed in detail through the use of isotope labeling expts. and quantum chem. calcns.  The exptl. and calcd. vibrational frequencies of adsorbed HC16O3-, DC16O3-, HC18O3-, HC16O18O2-, and HC18O16O2- indicate that bicarbonate bonds to the surface in a bridged structure.  There is some evidence from the mixed isotope expts. that following initial nucleophilic attack of OH, the formation of the final bicarbonate structure involves a proton transfer.  On the basis of energetic considerations, the proton transfer mechanism most likely occurs through an intermol. process involving either coadsorbed hydroxyl groups and/or carbonate. [on SciFinder(R)]</style></abstract><issue><style face="normal" font="default" size="100%">24</style></issue><notes><style face="normal" font="default" size="100%">CAPLUS AN 2006:504389(Journal)</style></notes></record></records></xml>