物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2014年
8期
1575-1580
,共6页
吴丹%张立敏%周丹娜
吳丹%張立敏%週丹娜
오단%장립민%주단나
光解离%一氧化二氮离子%Franck-Condon因子
光解離%一氧化二氮離子%Franck-Condon因子
광해리%일양화이담리자%Franck-Condon인자
Photodissociation%Nitrous oxide ion%Franck-Condon factor
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.
在超聲分子束條件下,利用360.50 nm的電離激光使N2O分子經由[3+1]共振增彊多光子電離(REMPI)產生純淨的N2O+(X2Π(000))分子離子,用另一束解離激光在230-275 nm範圍掃描穫得N2O+經由B2Πi←X2Π躍遷產生的光解碎片(NO+和N2+)激髮(PHOFEX)譜.穫得的光解碎片激髮譜可以歸屬為B2Πi(00n)←X2Π(000)序列躍遷.我們分彆將線性三原子分子離子N2O+中N-N伸縮振動簡化成NO和N之間的簡諧振動, N-O伸縮振動簡化成N2和O之間的簡諧振動,用諧振子的簡諧勢能麯線和波函數對N2O+分子離子X2Π和B2Πi電子態振動能級間躍遷的Franck-Condon因子進行計算,和實驗得到的碎片離子增彊譜實驗彊度進行比較,對前人給齣的分子數據(分子平衡覈間距)進行驗證,討論瞭N2O+經由B2Πi(00n)←X2Π(000)電子態躍遷的光解離機理和碎片離子的分支比.
재초성분자속조건하,이용360.50 nm적전리격광사N2O분자경유[3+1]공진증강다광자전리(REMPI)산생순정적N2O+(X2Π(000))분자리자,용령일속해리격광재230-275 nm범위소묘획득N2O+경유B2Πi←X2Π약천산생적광해쇄편(NO+화N2+)격발(PHOFEX)보.획득적광해쇄편격발보가이귀속위B2Πi(00n)←X2Π(000)서렬약천.아문분별장선성삼원자분자리자N2O+중N-N신축진동간화성NO화N지간적간해진동, N-O신축진동간화성N2화O지간적간해진동,용해진자적간해세능곡선화파함수대N2O+분자리자X2Π화B2Πi전자태진동능급간약천적Franck-Condon인자진행계산,화실험득도적쇄편리자증강보실험강도진행비교,대전인급출적분자수거(분자평형핵간거)진행험증,토론료N2O+경유B2Πi(00n)←X2Π(000)전자태약천적광해리궤리화쇄편리자적분지비.
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.