Gas-phase clustering reactions of NO2-, C2H3NO2-, C2H4NO2-, C2H5NO2- and C2H5NO4- with C2H5NO2

The gas-phase negative ion-molecule reactions of C2H5NO2 have been investigated by pulsed electron-beam high-pressure mass spectrometer. Association of C2H5NO2 with O2- leading to C2H5NO4- and its clusters was observed, increasing in relative importance with decreasing temperature. The clustering reactions A-(C2H5NO2)n-1+C2H5NO2[right arrow over left arrow]A-(C2H5NO2)n for A=NO2, C2H3NO2, C2H4NO2, C2H5NO2 and C2H5NO4 were studied, and the thermochemical data, [Delta]H°n-1,n and [Delta]S°n-1,n, for these reactions were determined. The decay rates found for CH3NO2-(CH3NO2)n and C2H5NO2-(C2H5NO2)n are significantly higher than those of other clusters studied. We consider the influence of the dipole-bound states of the core anions, CH3NO2- and C2H5NO2-, on the transport dynamics of their clusters.