Cluster Model Studies of Condensed Phase Phenomena
EMSL Project ID
25395
Abstract
This proposal is a continuation of research under EMSL User Proposal #8592. This program is aimed at obtaining a microscopic understanding of solution chemistry and solvation of negatively charged ions using cluster models in the gas phase. Our primary experimental technique is photoelectron spectroscopy coupled with electrospray ionization.1,2 Experimental and ab initio calculations are combined to 1) obtain a molecular-level understanding of the solvation and stabilization of singly and multiply charged anions important in the condensed phase; 2) understand the molecular processes and initial steps of dissolution of salt molecules in polar solvents; 3) probe the structure and dynamics of solution and air/solution interface. A central theme of this research program lies at obtaining a molecular-level understanding of environmental materials and solution chemistry, which is important to address issues related to waste storage, subsurface and atmospheric contaminant transport, and other primary DOE missions. Steady progress has been made to achieve the goals described above, and a selected set of publications are listed below.1-11Temperature is a known critical issue in gas phase spectroscopy and ion chemistry. Recently we have developed a second generation electrospray photoelectron spectroscopy apparatus, which is able to selectively trap ions under low temperature conditions.12,13 A low temperature trap is valuable to suppress thermal broadening in the photoelectron spectra and help stabilize weakly bound clusters. In addition, temperature dependent studies are possible, which can be used to investigate entropic effects on ion confirmations and isomer populations. We anticipate that the second generation electrospray photoelectron spectroscopy apparatus will significantly expand our capability and flexibility to study solution phase species in the gas phase, and propose specific tasks 1-4 in the following to address many novel and outstanding issues related to condensed phase phenomena.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2007-06-01
End Date
2010-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Stepwise hydration of the cyanide anion: A temperature-controlled photoelectron spectroscopy and ab initio computational study of CN−(H2O)n, n=2–5
Wang XB, K Kowalski, LS Wang, and SS Xantheas. 2010. "Stepwise hydration of the cyanide anion: A temperature-controlled photoelectron spectroscopy and ab initio computational study of CN-(H2O)n(n=2-5)." Journal of Chemical Physics 132(12):124306/1-10. doi:10.1063/1.3360306
Observation of Entropic Effect on Conformation Changes of Complex Systems under Well-Controlled Temperature Conditions
Wang XB, J Yang, and LS Wang. 2008. "Observation of Entropic Effect on Conformation Changes of Complex Systems Under Well-Controlled Temperature Condition." Journal of Physical Chemistry A 112(2):172-175. doi:10.1021/jp711205z
Photoelectron spectroscopy of anions at 118.2nm: Observation of high electron binding energies in superhalogens MCl4− (M=Sc, Y, La)
Yang J, XB Wang, X Xing, and LS Wang. 2008. "Photoelectron Spectroscopy of Anions at 118.2 nm: Observation of High Electron Binding Energies in Superhalogens MCI4- (M=Sc, Y, La)." Journal of Chemical Physics 128(20):Art. No. 201102. doi:10.1063/1.2938390
Imaging Intramolecular Coulomb Repulsions in Multiply Charged Anions
Xing X, XB Wang, and LS Wang. 2008. "Imaging Intramolecular Coulomb Repulsions in Multiply Charged Anions." Physical Review Letters 101(8):Art. no. 083003. doi:10.1103/PhysRevLett.101.083003