Journal of Physical Chemistry A, Vol.115, No.1, 25-29, 2011
Variable-Temperature Rate Coefficients for the Electron Transfer Reaction N-2(+) + H2O Measured with a Coaxial Molecular Beam Radio Frequency Ring Electrode Ion Trap
The neutral molecule temperature dependence of the rate coefficient for the electron transfer reaction from H2O to N-2(+) is determined using a coaxial molecular beam radio frequency ring electrode ion trap (CoMB-RET) method. The temperature of the N-2(+) ions was maintained at 100 K, while the effusive water beam temperature was varied from 300 to 450 K. The result demonstrates the neutral molecule rotational/translational energy dependence on the rate coefficient of an ion-dipolar molecule reaction. It is found that the rate coefficient in the above temperature range follows the prediction of the simplest ion-dipole capture model. Use of different buffer gas collisional cooling in both the ion source and the RET reveals the effects of both translational and vibrational energy of the N-2(+) ions.