GAS-PHASE CLUSTERING REACTIONS OF O-2(-), NO-, AND O- WITH N2O - ISOMERIC STRUCTURES FOR (NO-N2O)(-)

The gas-phase clustering reactions of O-2(-), NO-, and O- with N2O wer e studied with a pulsed electron beam high-pressure mass spectrometer. The formation of the covalent bond in the complexes (NO-N2O)(-) and ( O-N2O)(-) is suggested. The covalent character suggested in (NO-N2O)(- ) is in a marked contrast to the results from Bowen et al., who observ ed the largely intact NO- core in NO- (N2O)(n) using photoelectron spe ctroscopy. The presence of isomeric structures for (NO-N2O)(n))(-) was postulated by ab initio calculations. For the cluster ions, O-2(-)(N2 O)(n), NO-(N2O)(n), and O-(N2O)(n), the bond energies show an irregula r decrease with n = 2 --> 3, 3 --> 4, and 3 --> 4, respectively. This falloff indicates that these cluster ions have the cote plus surroundi ng molecules O-2(-)(N2O)(2)(N2O)(n-2), (NO-N2O)(-)(N2O)(2)(N2O)(n-3), and (O-N2O)(-)(N2O)(2)(N2O)(n-3) Ab initio optimized geometries are di scussed in relation to the measured binding energies.