U of M :: College of Liberal Arts :: Chemistry & Biochemistry :: Research & Teaching Faculty

Chemistry & Biochemistry
University of Mississippi
University, MS 38677
(662) 915-7301
(662) 915-7300 (fax)

Nathan Hammer

Assistant Professor

Contact Information

Office: 113 Coulter Hall
Phone: 662-915-3989
Email: nhammer AT olemiss.edu

Educational and Professional Background

Honors B.S. in Chemistry, University of Tennessee, 1998
Ph.D. Physical Chemistry, University of Tennessee, 2003
Postdoctoral Researcher, Yale University, 2003-2005
Intelligence Community Postdoctoral Fellow, University of Massachusetts, 2005-2007
Assistant Professor, University of Mississippi, 2007-present

Research Interests: Spectroscopy, energy and charge transfer, physical properties and structure of single molecules and small clusters of molecules and ions

Group Webpage

http://www.nathanhammer.com

Research Summary

When molecules interact noncovalently through hydrogen bonding or other electrostatic interactions, pi-pi interactions, or Van der Waals forces, their physical properties change. Although intermolecular interactions have received much attention recently at the ensemble level, the study of individual dimers, trimers and larger clusters (as well as binary and higher level interactions with other species) to reveal the intimate interactions leading to the bulk observables remains for the most part elusive. Here, we study the physical properties of interacting molecules in environments ranging from the single molecule to the bulk. Our spectroscopic capabilities include high resolution Raman spectroscopy of bulk materials, the study of size-selected clusters and aggregates in the gas phase using a mass spectrometer, and the use of single molecule techniques such as surface enhanced Raman spectroscopy and other laser-based spectroscopies to study single interacting molecular architectures. Such studies help answer long-standing questions involving the effects of intermolecular interactions on biologically relevant systems and also in developing devices incorporating conjugated organic molecules, to name a few examples. These studies will also allow for the tailoring of new nanoscale building blocks that would have physical properties dependent upon the number of molecules present.

Recent Publications

Only a few select publications are shown below. For a complete list of publications go to http://www.nathanhammer.com and click Research, or click here for a full cv.

A. Muraoka, Y. Inokuchi, N. I. Hammer, J-W. Shin, M. A. Johnson, and T. Nagata,
"Structural Evolution of the (CO₂)_n H₂O)]^- Cluster Anions: Quantifying the Effect of Hydration on the Excess Charge Accommodation Motif" Journal of Physical Chemistry A, 113, 8942–8948 (2009).

J. R. Roscioli, N. I. Hammer, M. A. Johnson, K. Diri and K. D. Jordan,
"Exploring the correlation between network structure and electron binding energy in the (H₂O)₇^- cluster through isomer photoselected vibrational predissociation spectroscopy and ab initio calculations: Addressing complexity beyond types I-III" Journal of Chemical Physics, 128, 104314 (2008).

M. Y. Odoi, N. I. Hammer, H. P. Rathnayake, P. M. Lahti, and M. D. Barnes,
"Single Molecule Studies of a Model Fluorenone," ChemPhysChem, 8, 1481 (2007).

N. I. Hammer, T. Emrick, and M. D. Barnes,
"Quantum dots coordinated with conjugated organic ligands: new nanomaterials with novel photophysics," Nanoscale Research Letters, 2, 282 (2007). (Invited Review)

M. Y. Odoi, N. I. Hammer, K. T. Early, K. D. McCarthy, R. Tangirala, T. Emrick and M. D. Barnes,
"Fluorescence lifetimes and correlated photon statistics from single CdSe/oligo-(phenylene vinylene) composite nanostructures," Nano Letters, 9, 2769 (2007).

M. Y. Odoi, N. I. Hammer, K. Sill, T. Emrick, and M. D. Barnes,
"Observation of enhanced energy transfer in individual quantum dot-oligophenylene vinylene nanostructures," Journal of the American Chemical Society, 128, 3506 (2006). (Communication)

N. I. Hammer, K. T. Early, K. Sill, M. Y. Odoi, T. Emrick, and M. D. Barnes,
"Coverage-mediated suppression of blinking in solid state quantum dot-conjugated organic composite nanostructures," Journal of Physical Chemistry B, 110, 14167 (2006). (Cover Article)

R. Hassey, E. Swain, N. I. Hammer, D. Venkataraman, and M. D. Barnes,
"Probing the Chiroptical Response of a Single Molecule," Science, 314, 1437 (2006).
(Published online November 2, 2006 in Sciencexpress)

N. I. Hammer, J. R. Roscioli, and M. A. Johnson,
"Identification of two distinct electron binding motifs in the anionic water clusters: A vibrational spectroscopic study of the (H₂O)₆^- isomers," Journal of Physical Chemistry A, 109, 7896 (2005). (Cover Article)

N. I. Hammer, S. G. Stepanian, L. Adamowicz, and R. N. Compton,
"Isotope Effects in Dipole-Bound Anions of Acetone," Physical Review Letters, 94, 153004, (2005).

J. M. Headrick, E. G. Diken, R. S. Walters, N. I. Hammer, R. A. Christie, J, Cui, E. M. Myshakin, M. A. Duncan, M. A. Johnson, and K. D. Jordan,
"Spectral signatures of hydrated proton vibrations in water clusters," Science, 308, 1765 (2005).

N. I. Hammer, J. R. Roscioli, M. A. Johnson, E. M. Myshakin, and K. D. Jordan,
"Infrared Spectrum and Structural Assignment of the Water Trimer Anion," Journal of Physical Chemistry A, 109, 11526 (2005).

C. Desfrançois, Y. Bouteiller, J. P. Schermann, D. Radisic, S. T. Stokes, K. H. Bowen, N. I. Hammer, and R. N. Compton,
"Long-range electron binding to quadrupolar molecules," Physical Review Letters, 92, 083003 (2004).

J-W. Shin, N. I. Hammer, E. G. Diken, M. A. Johnson, R. S. Walters, T. D. Jaeger, M. A. Duncan, R. A. Christie, and K. D. Jordan,
"Infrared signature of structural motifs associated with the H⁺(H₂O)_n, n = 6-29, clusters," Science, 304, 1137 (2004).
(Published online April 29th in Sciencexpress)

N. I. Hammer, J.-W. Shin, J. M. Headrick, E. G. Diken, J. R. Roscioli, G. H. Weddle, and M. A. Johnson,
"How do small water clusters bind an excess electron?," Science, 306, 675 (2004).
(Published online September 16, 2004 in Sciencexpress)