CO(a)+NO(X)传能体系中的新传能通道(英文)

A New Product Channel in the Energy Transfer of CO(a,ν ′)+NO(X)

在相对碰撞平动能为 0 .0 5eV的分子束实验条件下 ,研究了亚稳态CO(a) +NO(X)的E E传能通道 .通过测量和分析交碰区的传能发射光谱 ,在 780和 860nm处观测到了NO(b -a)跃迁Ogawa带的△v =+ 4和△v =+ 3序的发射光谱 .从而首次在实验上直接证实了传能过程中第四通道的存在 (CO (a) +NO(X)→CO (X) +NO(b) ) .这一通道的发现解释了前人测量到的在CO(a)与NO(X)碰撞传能过程中CO(a)的猝灭速率远大于NO(A ,B)生成速率的实验结果 ,并进一步证实了这一“经典”E

Under single-collision conditions, a beam of meta st able molecules CO(a,ν′) generated by DC discharge was allowed to collide with a beam of NO(X) at a fixed angle of 90 o. The collision-induced emission from the interaction region was collected at right angles to the beam plane by a lens set and dispersed by a 1 m monochromator where a cooled photomultiplier tube wa s mounted on the exit slit. The signal from the PMT was transmitted via a discri minator, a photon counter and a boxcar integrator into a computer for storing an d processing. Two broadband emissions were observed around the wavelengths of 7 80 and 860 nm, which can be assigned to NO(b-a) Ogawa bands △v=+4 and+3 se quences, respectively, and referred to the spectroscopic data given by Huber. At the collision energy of 0.05 eV in the present experimental conditions, the ele ctronic energy of CO(a,ν′=0)( 6.01 eV ) was not enough to excite NO(X) to NO (b,ν′=4,5)(△E>6.11 eV). So, what was in act in the energy transfer was th e vibrational excitation of CO(a,ν′>0), and the higher the vibrational excitat ion of CO(a,ν′) was, the stronger the emission intensity of NO(b-a) could be obtained. It is thought that electron exchange between CO(a) and NO(X) may be op erative through the formation of a complex OCNO. The newly discovered formation of NO(b) channel could be well explained considering the energy conservation, sp in conservation and electron exchange mechanism.