?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F7663%2F&rft.title=VIBRATIONAL+SPECTRA+AND+n-BODY+DECOMPOSITION+ANALYSESOF+WATER+CLUSTERS&rft.creator=Cui%2C+Jun&rft.description=The+hydrated+proton+lies+at+the+heart+of+several+key+charge+transport+processes+in+chemistry+and+biology%2C+and+yet+the+molecular+level+description+of+proton+accommodation+remains+elusive.+Both+H3O%2B+(so+called+Eigen)+and+(H2O%C2%B7%C2%B7%C2%B7H%C2%B7%C2%B7%C2%B7OH2)%2B+(so+called+Zundel)+have+long+been+thought+to+play+essential+roles+in+the+proton+transfer+process.+We+characterize+the+hydrated+proton+with+a+%22bottom+up%22+approach+to+monitor+the+spectral+evolution+of+the+proton+accommodation+motif+as+water+molecules+are+sequentially+added+to+the+H3O%2B+ion.+It+is+found+that+a+highly+symmetrical+structure+is+necessary+to+observe+the+Eigen+ion.+Small+asymmetries+in+the+hydration+structure+around+the+H3O%2B+core+result+in+preferential+localization+of+the+excess+charge+on+one+or+two+of+the+hydrogen+atoms.+This+extreme+response+to+symmetry+breaking+readily+explains+the+lack+of+a+crisp+spectral+signature+of+the+hydrated+proton+in+the+bulk.+Density+functional+theory+is+used+to+study+the+relative+stability+of+various+isomers+of+(H2O)n+%C2%B7+H%2B%2C+n+%3D+4-12%2C+allowing+for+the+influence+of+vibrational+zero+point+energy+and+finite+temperature+effects.+Comparison+of+experimental+spectra+with+and+without+Ar+tagging+shows+that+the+inclusion+of+Ar+atoms+has+little+effect+on+the+frequencies.Two+low-energy+minima+of+(H2O)21+with+very+different+H-bonding+arrangements+have+been+investigated+with+the+B3LYP+density+functional+and+RIMP2+methods%2C+as+well+as+with+the+TIP4P%2C+Dang-Chang%2C+AMOEBA%2C+and+TTM2-F+force+fields.+Insight+into+the+role+of+many-body+polarization+for+establishing+the+relative+stability+of+the+two+isomers+is+provided+by+an+n-body+decomposition+of+the+energies+calculated+using+the+various+theoretical+methods.&rft.date=2007-06-20&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F7663%2F1%2Fcui_etd2007.pdf&rft.identifier=++Cui%2C+Jun++(2007)+VIBRATIONAL+SPECTRA+AND+n-BODY+DECOMPOSITION+ANALYSESOF+WATER+CLUSTERS.++Doctoral+Dissertation%2C+University+of+Pittsburgh.++++(Unpublished)++