Prediction of QCM gas sensor responses and calculation of electrostatic contribution to sensor responses using a computational chemistry method

When we construct an odor sensing system using a quartz crystal microbalance (QCM) odor sensor array, it is important to know the properties of sensing films coated on those electrodes and select the optimum combination of sensors in the array. However, they have not been characterized well enough to predict the sensor responses without any experiment. Then, we tried to predict sensor responses using a computational chemistry method. We have so far succeeded in predicting the responses using sensing films of typical liquid gas chromatography (GC) stationary phase materials to various kinds of gases and a few perfumes. In this study, we calculated the amount of sorbed gas molecules into the typical solid material of GC and the amount of sorbed perfumes into various sensing films, and it was found that this computational prediction method is useful in those cases. Next, we tried to evaluate the contribution of single interaction energy term to the sorption using this method although it cannot be revealed through the experiment. It was found from the results that the contribution of electrostatic interaction to the sorption can almost be evaluated and this calculation method is useful for knowing the properties of gases and sensing films.