Prediction of quartz crystal microbalance gas sensor responses using a computational chemistry method

The characteristics of quartz crystal microbalance (QCM) gas sensors depend on the kinds of sensing films coated on their electrodes. Although it is e ssential, in an odor sensing system, to know the characteristics of various sensing films, they have not been characterized well enough to predict the sensor responses without any experiments. Hence, we tried to predict senso r responses using a computational chemistry method. The prediction of the s ensor responses enables us to easily design the combination of sensors in a n odor sensing system. In this study, we calculated the amounts of gas mole cules such as alcohols, aromatics, ketones, esters, alkanes and perfumes so rbed into typical sensing films, and compared them with experimental result s. Consequently, it was found that the tendency of QCM sensor responses to vapors over a wide range of odor intensity could almost be predicted by a c omputational chemistry method if the chemical structures of the film and ga s molecules are known. Moreover, the effects of sensing film polarities app eared significant in both simulations and experiments. (C) 1999 Elsevier Sc ience S.A. All rights reserved.