Verification of the insertion mechanism of N(2 2D) into H–H bonds by the vibrational state distribution measurement of NH(X  3Σ−,0⩽v″⩽3)

Abstract

Resonance-state selective photodissociation of OCS (2 1 Σ + ): Rotational and vibrational distributions of CO fragmentsThe nascent vibrational state distribution of NH(X 3 ⌺ Ϫ ) radicals produced in the reaction of N( 2 D) with H 2 was determined by employing a pulsed laser technique. N( 2 D) was produced by two-photon dissociation of NO, while NH(X 3 ⌺ Ϫ ) was detected by laser-induced fluorescence. Off-diagonal transitions of the A -X system were employed to probe NH(X 3 ⌺ Ϫ ,vЉу2) because of the predissociative nature of the upper state. The vibrational distribution was determined to be 10.0(vЉϭ0): 8.0Ϯ1.0(vЉϭ1): 5.0Ϯ0.7(vЉϭ2): 2.5Ϯ0.5(vЉϭ3). This distribution is much cooler than that obtained by infrared emission measurements, but is similar to that of recent quasiclassical trajectory calculations as well as that of three dimensional quantum calculations based on an ab initio potential energy surface. The agreement with theoretical results suggests that the reaction proceeds via an insertive process.

A Quantum Wave Packet Dynamics Study of the N(2D) + H2 Reaction

“…Although evidence of an abstraction mechanism for this reaction has been reported in an early experimental work 1 on the vibrational distribution of the NH product as well as in several calculations, 2,3 it is now widely recognized that such a reaction belongs to the family of insertion reactions occurring on potential energy surfaces with deep wells. For this reason, experimental and theoretical work [4][5][6][7][8][9][10][11][12][13][14][15] has recently been diverted to it from the prototype O( 1 D) + H 2 reaction which has been the most extensively studied thus far. [16][17][18][19] The first global potential energy surface for the 1 2 A′′ state of NH 2 favoring an insertion mechanism for the title reaction has been reported by Pederson et al 4 using the reproducing kernel Hilbert space (RKHS) interpolation method based on high level ab initio points.…”

CRITICAL REVIEW OF N, N + , N + 2 , N ++ , And N ++ 2 MAIN PRODUCTION PROCESSES AND REACTIONS OF RELEVANCE TO TITAN'S ATMOSPHERE

“…The only exothermic reactive channel is the one leading to NH in its X 3 Σ − electronic ground state and atomic hydrogen. Of potential relevance for the atmosphere of Titan is the product energy partitioning, that has been determined in the studies of Umemoto et al (2000) and Balucani et al (2006), which show that NH vibrational states are populated up to v = 3 (Umemoto et al 2000). Let us note that the vibrational excitation of NH can significantly change its capability to undergo subsequent reactions.…”

Selective production and kinetic analysis of thermally equilibrated N2(B3Πg, v = 0) and N2(W3Δu, v = 0)

“…The detection procedure of NH was the same as those described elsewhere. 31,[48][49][50] Fig. 5 Temporal profiles of the (0,1) band of the NO(A-X) emission in Xe/N 2 /NO (upper solid line) and Xe/N 2 /NO/H 2 (lower solid line) systems.…”