The dynamics of the prototypical insertion reaction N(2D) + D2 have been investigated in a combined experimental and theoretical study. Angular and velocity distributions of the ND product have been obtained in crossed molecular beam experiments with mass spectrometric detection at two collision energies (Ec ) 3.8 and 5.1 kcal mol-1). The center-of-mass product angular and translational energy distributions have been derived; at both Ec’s, the former is found to be nearly backward-forward symmetric, reflecting an insertion dynamics, and the latter corresponds to a fraction of total available energy released in translation of 32%, indicating that the ND product is highly internally excited. Quasiclassical trajectory (QCT) calculations were performed on an accurate potential-energy surface obtained from large-scale ab initio electronic structure computations, and the results were compared to experiment. Generally good agreement was found between the experimental results and the theoretical predictions; however, small, yet significant, discrepancies point to some inaccuracy of the QCT treatment, calling for a quantum scattering study of the title reaction.
The dynamics of the N( 2 D)+D 2 reaction from crossed-beam and quasiclassical trajectory studies
BALUCANI, Nadia;CARTECHINI, Laura;CASAVECCHIA, Piergiorgio;VOLPI, GIAN GUALBERTO;
2001
Abstract
The dynamics of the prototypical insertion reaction N(2D) + D2 have been investigated in a combined experimental and theoretical study. Angular and velocity distributions of the ND product have been obtained in crossed molecular beam experiments with mass spectrometric detection at two collision energies (Ec ) 3.8 and 5.1 kcal mol-1). The center-of-mass product angular and translational energy distributions have been derived; at both Ec’s, the former is found to be nearly backward-forward symmetric, reflecting an insertion dynamics, and the latter corresponds to a fraction of total available energy released in translation of 32%, indicating that the ND product is highly internally excited. Quasiclassical trajectory (QCT) calculations were performed on an accurate potential-energy surface obtained from large-scale ab initio electronic structure computations, and the results were compared to experiment. Generally good agreement was found between the experimental results and the theoretical predictions; however, small, yet significant, discrepancies point to some inaccuracy of the QCT treatment, calling for a quantum scattering study of the title reaction.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.