Theoretical modeling of organic molecules for X-ray absorption spectroscopy

PHYS 560

Chen Chen, cxchen@wesleyancollege.edu and David C. Edwards, dedwards@wesleyancollege.edu. Chemistry and Physics, Wesleyan College, 4760 Forsyth Road, Macon, GA 31210
Natural organic macromolecules are implicated in almost all biochemical and environmental processes, yet their reactivity in different chemical environments is not well understood due to their complex compositions and structural variations. X-ray absorption spectroscopy (XAS) is a relatively new technique that examines the functional group characteristics of organic macromolecules; however, fundamental theoretical studies that assess functional group variations with this technique at the N-K edge are lacking. In order to increase our understanding of XAS, this study has evaluated a series of smaller solid-phase organic compounds with theoretical and experimental XAS measurements. Initial results show agreement between the theoretical models obtained with StoBe and the experimentally observed energy transitions. However, the spectral overlap of functional group transitions (e.g. amide and imino) makes it difficult to unambiguously assign functional groups in macromolecules. Further theoretical calculations, combined with knowledge of the macromolecular system, will make XAS a more viable spectroscopic tool.
 

Sci-Mix
8:00 PM-10:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Sci-Mix

Division of Physical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008