(174f) Carbohydrate Conformational Cartography

Modeling accurate structures of transition states has been a boon to reaction path analysis, allowing researchers to tease apart elementary steps from complex reaction mechanisms. This knowledge can then be used to built microkinetic models and inform efforts to catalyze desirable reactions, such as conversion of biomass into renewable fuels and chemicals. Of course, modeling transition structures (TSs) is inherently more difficult problem than modeling local minima. Ab initio methods to search the potential energy surface for low-energy TSs quickly become prohibitively expensive for large, flexible molecules such as carbohydrates, necessitating the use of approximate methods that are fitted to data on local minima. We present our investigations into the promise and pitfalls of mapping reaction paths with density functional theory and semi-empirical methods.