Physical Chemistry; Molecular Dynamics
BS, University of Missouri-Rolla, 1974
PhD, University of California, Berkeley, 1979
Curators' Distinguished Teaching Professor Emeritus, University of Missouri-Columbia, 2015-present
Curators' Distinguished Teaching Professor, University of Missouri-Columbia, 2010-2015
Professor, University of Missouri-Columbia, 2003-present
Associate Professor, University of Missouri-Columbia, 1987-2003
Assistant Professor, University of Missouri-Columbia, 1981-1987
Postdoctoral Fellow, Los Alamos National Laboratory, 1979-1981
Honors and Awards
Honorary Professional Degree in Chemistry, Missouri University of Science and Technology, 2011
Governor’s Award for Excellence in Education, 2010
Fellow of the American Chemical Society, 2009
Presidential Award for Outstanding Teaching, 2009 (UM System)
E. Ann Nalley Midwest Award for Volunteer Service, 2008 (American Chemical Society)
Excellence in Advising Award, 2005 (MU Advisors Forum and Office of the Provost)
Excellence in Education Award, 1999 (MU Division of Student Affairs)
William T. Kemper Fellow for Excellence in Teaching, 1993 (MU campus)
AMOCO Foundation Undergraduate Teaching Award, 1987 (MU campus)
Professional Activities (partial listing of current activities)
American Chemical Society
- Board of Directors, District V Director
- Councilor (ex officio)
- Trustee, Group Insurance Plans for ACS Members (Chair of the Board of Trustees)
- Committee service: Public Affairs and Public Relations (Chair), Audits, Board Executive Committee, Strategic Planning Committee
- Historian and Webmaster, Midwest Region
Alpha Chi Sigma, Professional Chemistry Fraternity
- Parliamentarian, Past National President
Alpha Chi Sigma Educational Foundation
- Foundation Member and Trustee
The Honor Society of Phi Kappa Phi
- University of Missouri Chapter, Treasurer and Past President
Our primary research thrust in recent years has been directed toward developing an understanding of how thermal motion affects the structures and stabilities of supramolecular complexes. These complexes, which are bound by non-covalent intermolecular forces, have been shown in experiments conducted by the Atwood group and others to yield materials having unusual properties. For example, a specially prepared crystal form of the calixarene macrocycle—calixarene is a cup-shaped molecule that can trap a small molecule within its cavity—sorbs atmospheric gases even though it is without the well-defined pore structure found in zeolites or metal-organic frameworks (MOFs). These crystals furthermore exhibit selectivity: carbon dioxide is preferentially retained when the crystals are exposed to a mixture of carbon dioxide and molecular hydrogen. The Atwood group also has shown that a similar macrocycle, pyrogallolarene, when reacted with solutions of transition metal salts, often yields metal-seamed capsules, which could serve as micro-reactors or as vessels for selectively transporting drug molecules to tumor or infection sites. The challenge here will be to devise capsules with larger and larger interior volumes, but meeting this challenge requires that we understand the dynamics of the capsules themselves as well as the dynamics of the sequestered guest species. The latter consideration is significant because NMR is conventionally used to investigate the guest, and the mobility of the guest on the NMR time scale affects the number of resonances observed.
As an example of this work, a snapshot is shown below of a zinc-seamed pyrogallolarene dimer capsule with exo pyridine ligands and a sequestered protonated pyridine molecule (two orientations are depicted).
We also are investigating the dynamics of the macrocycles themselves. Formation of dimeric capsules requires that the macrocycles adopt a cone conformation, but there is no guarantee that the synthesis of the macrocycles yields exclusively (or even primarily) the desired conformer. Thus, by identifying the conditions under which a non-cone conformer will transition to the cone conformer, we will assist in the development of more efficient syntheses of these systems.
In addition to the work carried out in collaboration with the Atwood and Deakyne groups (the latter group focusing on structural characterizations and energetics determined from electronic structure calculations), we have joined the Deakyne group in examining various species of interest to the Jurisson group, species that have been shown to complex radionuclides such as technetium and rhenium. One of our contributions to this research program is an investigation of the effect of explicit solvent molecules on molecular conformation. The solvent environment can play a very significant role, for example, in determining the orientation of amino acid side chains that are involved in substrate binding.
J. E. Adams, J. R. Cox, A. J. Christiano, and C. A. Deakyne, Molecular Dynamics of Host-Guest Complexes of Small Gas Molecules with Calixarenes, J. Phys. Chem. A 2008, 112, 6829-6839.
S. J. Dalgarno, T. Szabo, A. Siavosh-Haghighi, C. A. Deakyne, J. E. Adams and J. L. Atwood, Exploring the Limits of Encapsulation within Hexameric Pyrogallolarene Nano-capsules, Chem. Commun. (Cambridge, U. K.) 2009, 1339-1341.
M. D. Breite, J. R. Cox and J. E. Adams, Energetics of Intercavity Diffusion in a Simple Model of a Low-Density p-tert-Butylcalixarene Crystal, J. Am. Chem. Soc. 2010, 132, 10996-10997.
C. M. Mayhan, T. J. Szabo, J. E. Adams, and C. A. Deakyne, Multiligand Zinc(II) Hydroxide Complexes: Zn(OH)2X2Y and Zn(OH)2X1,2Y2; X = H2O, CH3OH and Y = NH3, C5H5N, Comput. Theor. Chem. 2012, 984, 19-25.
H. Kumari, L. Erra, A. C. Webb, P. Phatt, C. L. Barnes, C. A. Deakyne, J. E. Adams, L. J. Barbour, and J. L. Atwood, Pyrogallolarenes as Frustrated Organic Solids, J. Am. Chem. Soc. 2013, 135, 16963-16967.
C. Mayhan, T. J. Szabo, J. E. Adams, and C. A. Deakyne, Mononuclear and Polynuclear 5-Coordinate Zinc(II) Model Complexes: A Quantum Chemical Calibration Study of Their Structure and Energy, Struct. Chem. 2013, 24, 2089-2099.