The Water Hexamer Craig Tainter Skinner Group University of Wisconsin-Madison

Introduction

Water Clusters B. Temelso, K. A. Archer and G. C. Shields CCSD(T)/CBS (kcal/mol)

Theory K. Liu, M. Brown, C. Carter, R. Saykally, J. Gregory, and D. Clary C. Perez, M. Muckle, D. Zaleski, N. Seifert, B. Temelso, G. Shields, Z. Kisiel and B. Pate D. M. Bates and G. S. Tschumper Experiment R. Kumar, F.-F. Wang. G. R. Jenness and K. D. Jordan Binding Energies (kcal/mol) Binding Energies relative to Prism (kcal/mol)

E3B Water Model C. Tainter, P. Pieniazek, Y.-S. Lin and J. Skinner

Structure

Structure and Energetics No Prism! R. Kumar, F.-F. Wang, G. R. Jenness and K. D. Jordan R. M. Olson, J. L. Bentz, R. A. Kendall, M. W. Schmidt, and M. S. Gordon E. E. Dahlke, R. M. Olson, H. R. Leverentz and D. G. Truhlar D. M. Bates and G. S. Tschumper P. T. Kiss and A. Baranyai 2-Body 3-Body Energies in kcal/mol

Calculating Infrared Spectra Mixed quantum/classical approach – Need frequencies and couplings F. Li and J. Skinner

OH stretch spectroscopy T = 0 K M. Losada and S. Leutwyler J. Kim and K. S. Kim

Inherent structures and finite temperature spectroscopy

Comparison to Experiment 40 K C. Steinbach, P. Andersson, M. Melzer, J. K. Kazimirski, U. Buck, and V. Buch

Comparison to Experiment 60 K C. Steinbach, P. Andersson, M. Melzer, J. K. Kazimirski, U. Buck, and V. Buch

Comparison to Experiment 80 K E. G. Diken, W. H. Robertson and M. A. Johnson

Hydrogen Bonding K. Ohno, M. Okimura, N. Akai, and Y. Katsumoto

Hydrogen Bonding and Spectral Density

Conclusions Determined most stable hexamer isomers using E3B water model. Used MD simulations to learn about free energies of hexamers. Calculated OH stretch spectra. OH stretch frequency highly correlated with donor – acceptor character in both hexamer and liquid!

Acknowledgements Jim Skinner Scott Gruenbaum Lu Wang Liang Shi Josh Carr Yicun Ni Zak Kann