在超声分子束条件下，利用360.50 nm的电离激光使N2O分子经由[3+1]共振增强多光子电离(REMPI)产生纯净的N2O+(X2Π(000))分子离子，用另一束解离激光在230-275 nm范围扫描获得N2O+经由B2Πi←X2Π跃迁产生的光解碎片(NO+和N2+)激发(PHOFEX)谱.获得的光解碎片激发谱可以归属为B2Πi(00n)←X2Π(000)序列跃迁.我们分别将线性三原子分子离子N2O+中N-N伸缩振动简化成NO和N之间的简谐振动， N-O伸缩振动简化成N2和O之间的简谐振动，用谐振子的简谐势能曲线和波函数对N2O+分子离子X2Π和B2Πi电子态振动能级间跃迁的Franck-Condon因子进行计算，和实验得到的碎片离子增强谱实验强度进行比较，对前人给出的分子数据(分子平衡核间距)进行验证，讨论了N2O+经由B2Πi(00n)←X2Π(000)电子态跃迁的光解离机理和碎片离子的分支比.%Photofragment (NO+and N2+) excitation (PHOFEX) spectra of N2O+via B2Πi←X2Πtransitions was obtained over the wavelength range from 230 to 275 nm by preparing N2O+(X2Π(000)) ions via [3+1] resonance enhanced multiphoton ionization of N2O molecules at 360.50 nm. On the basis of the approximation of harmonic oscil ation between N and NO or between N2 and O, the Franck-Condon factors for the B2Πi(00n)←X2Π(000) transitions of N2O+ions were calculated using the potential curves and wavefunctions of the harmonic oscil ator. The results of such calculations were compared with the photodissociation spectra of the B2Πi(00n)←X2Π(000) transition so as to estimate the validity of the rotational constants and the bond length of the B2Πi state obtained from previous studies. The photodissociation mechanism of the B2Πi(00n)←X2Π(000) transitions of N2O+ions and the product branching ratios were also discussed.
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