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1.
丙酮分子的分质量共振多光子电离光谱及多光子电离—离解机理研究 总被引:3,自引:0,他引:3
用多光子电离飞行时间质谱法三光子与丙酮分子3d形态和4s态共振的激光波长区域获得了丙酮分子的共振多光子电离分质量多光子电离(MPI)光谱和飞行时间质谱,实验观察到的主要产物是CH3CO^+和CH^+3,还观察到了少量的C^+,CH^+,CH^+2和CHO^+,在实验的激光波长范围内未见到母体离子,分质量多光子电离光谱具有相似的光谱结构,几个主要谐峰分别对应着(n0,3d)和(n0,4s)里德堡跃迁 相似文献
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首次研究了二乙胺分子的多光子电离过程。实验是在无碰撞的高真空状态下进行的,用飞行时间质谱仪获得了染料激光器在464-486nm波段的二乙胺分子MPI质谱(MS)。母体离子由经(nN,3s)里德堡态的(2+2)共振增强多光子电离(REMPI)产生。各种离子强度体随激光波长和强度的变化表明,碎片离子阶梯模型产生了二乙胺分子MPI的碎片离子分布。 相似文献
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采用超声分子束技术,以飞行时间质谱仪,在410~371nm内着重检测了不同波长、不同能量的激光对气相Si(CH3)4分子多光子电离(MPI)飞行时间(TOF)质谱产物分布的影响。根据实验结果,对Si(CH3)4分子多光子解离电离可能经历的通道和反应机理进行了讨论。 相似文献
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报道了乙胺分子在440-475nm波长范围内多光子电离(MPI)质谱(MS)研究结果。碎片离子主要由母体离子碎裂模式产生。母体离子CH3CH2NH2由经3s里德堡态的(2+2)共振多光子电离产生后,大部分发生β键断裂,形成CH2=N+H2离离子,还有一部分再吸收一个光子,通过C-H(CH2)键的断裂产生了CH3CH-NH2离子。CH3CH=NH2和CH2=NH2离子最容易发生的碎裂过程是脱去氢分子 相似文献
5.
用原子束技术—激光共振电离—飞行时间质谱探测离子信号的方法,观察到了原子束中镁Mg3s21S0-3s3d1D2单光子电四极矩共振跃迁,并对实验结果进行了判断和分析。 相似文献
6.
呋喃分子在450nm的多光子电离碎片化动力学 总被引:2,自引:0,他引:2
用分质量多光子电离光谱和飞行时间质谱研究了呋喃分子在440-460nm之间的多光子电离碎片化动力学。实验观察到的主要离子是C^+,C^+2,CHO^+和C3H^+3,在实验允许的功率范围内没有观察到母离子C4H4O^+。跟踪这些离子得到的MPI光谱具有相似的光谱特征,而且可以归属于母体分子三光子从基电子态到5p,5d,5f等里德堡态的跃迁,说明这是呋喃分子MPIF过程的速度控制步骤。根据热力学数据 相似文献
7.
镁Mg2s^21S0—3s3d^1D2单光子电四极矩跃迁的研究 总被引:2,自引:2,他引:0
用原子束技术-激光共振电离-飞行时间质谱探测离子信号的方法,观察到了原子束中镁Mg3s^21S0-3s3d^1D2单光子电四极矩共振跃迁,并对实验结果进行了判断和分析。 相似文献
8.
乙胺分子的多光子电离过程质谱研究 总被引:1,自引:0,他引:1
报道了乙胺分子在440~475nm波长范围内多光子电离(MPI)质谱(MS)研究结果。碎片离子主要由母体离子碎裂模式产生。母体离子CH3CH2N+·H2由经3s里德堡态的(2+2)共振多光子电离产生后,大部分发生β键断裂,形成CH2=N+H2离子,还有一部分再吸收一个光子,通过C-H(CH2)键的断裂产生了CH3CH=N+H2离子。CH3CH=N+H2和CH2=N+H2离子最容易发生的碎裂过程是脱去氢分子,分别产生C2H4N+(分子式)离子和CH≡N+H离子。 相似文献
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紫激光作用下四甲基硅的光谱和质谱研究 总被引:5,自引:0,他引:5
本文利用平行板电极装置及飞行时间质谱仪相结合的方法对四甲基硅进行了多光子电离(MPI)光谱及飞行时间(TOF)质谱的研究。得到了激光激发波长在402~392nm内的多光子电离光谱,获得了某些波长处的飞行时间质谱,并据此讨论了该分子在这个区域内可能的MPI机理。 相似文献
11.
We report the results of a study on the vibrational structure in the (n, 3s) Rydberg state of iso-butanal, carried out via 2+1 multiphoton ionization spectroscopy in a supersonic expansion. Spectra were recorded for both the normal species, (CH(3))(2)CHCHO, and the deuterated isotopomer, (CH(3))(2)CDCHO. The spectra show a complicated vibrational pattern attributable to the gauche (C(1)) conformer which is known to be 250 cm(-1) lower in energy than the more symmetric trans (C(s)) conformer. The spectra are dominated by the low-frequency formyl torsion which appears in combination with the two methyl torsions (in-phase and out-of-phase) and with several skeletal modes. Vibrational assignments have been aided by ab initio calculations of the (n, 3s) Rydberg state. Copyright 2001 Academic Press. 相似文献
12.
我们用脉冲光学-光学双共振荧光激发谱(OODR),测量了在35500-38000cm^-1能量范围内的里德堡态,观察到^7Li23^1Ⅱg态的10个振动能,本文观测的3^1Ⅱg态的146条激发谱线进行了归属,得到了新的Dunhm常数,RKR势能曲线以及A^1∑u^ 到3^1Ⅱg态跃迁的夫兰克-康登因子,并且讨论了3^1Ⅱg态的双重分裂以及与附近里德堡态F(4)^1∑g^ ,5^1∑g^ ,6^1∑g^ 和G(2)^1Ⅱg的微扰,发现在我们的实验精度下(0.2cm^-1)3^1Ⅱg态掇重分裂可以忽略。 相似文献
13.
利用里德堡氢原子飞渡时间谱的方法,进行了甲基自由基在212.5nm 的光解动力学的实验研究.甲基自由基来自于碘甲烷分子在266nm 的光分解.实验测量了不同振动态的甲基自由基通过3s 电子激发态解离的产物 CH_2自由基的平动能分布和角分布,并从平动能分布得到了 CH_2自由基的转动布居.实验同时详细地研究了母体分子甲基自由基的振动和转动激发对光解动力学的影响.实验结果表明母体分乙甲基自由基的伞形振动对于产物的转动激发和角分布均有较大的影响,而母体分子的转动激发只对产物的角分布有较明显的影响. 相似文献
14.
Spectroscopic observation of resonant electric dipole-dipole interactions between cold Rydberg atoms
Afrousheh K Bohlouli-Zanjani P Vagale D Mugford A Fedorov M Martin JD 《Physical review letters》2004,93(23):233001
Resonant electric dipole-dipole interactions between cold Rydberg atoms were observed using microwave spectroscopy. Laser-cooled 85Rb atoms in a magneto-optical trap were optically excited to 45d(5/2) Rydberg states using a pulsed laser. A microwave pulse transferred a fraction of these Rydberg atoms to the 46p(3/2) state. A second microwave pulse then drove atoms in the 45d(5/2) state to the 46d(5/2) state, and was used as a probe of interatomic interactions. The spectral width of this two-photon probe transition was found to depend on the presence of the 46p(3/2) atoms, and is due to the resonant electric dipole-dipole interaction between 45d(5/2) and 46p(3/2) Rydberg atoms. 相似文献
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We predict the existence of a ubiquitous class of long-range molecular Rydberg states, whose Born-Oppenheimer potential curves are oscillatory in nature. These oscillations reflect the nodal structure of the atomic Rydberg state wave functions. The temperature and density of atoms in a Bose-Einstein condensate are particularly favorable for the laser excitation of ultra-long-range vibrational bound states localized at internuclear distances in the range 10(3)- 10(5) a.u. A surprising trilobitelike class of polar homonuclear diatomics should exhibit electric dipole moments in the kilodebye range. 相似文献
17.
《Journal of Molecular Spectroscopy》1987,122(2):269-274
The 3s Rydberg state of pyrimidine is seen as a two-photon resonant structure on its three-photon ionization spectrum. The vibrational structure is analyzed and compared with the VUV absorption and photoelectron spectra. 相似文献
18.
Br2分子里德堡态的高分辨转动谱研究 总被引:2,自引:2,他引:0
用窄线宽(0.08cm^-^1)脉冲可调谐紫外激光和(2+1)多光子电离方法测量了Br2的里德堡(Rydberg)态光谱,在70000-71500cm^-^1范围内,获得了溴分子[П3/2]4d振动系列,测量(v',v”)=(1,0),(2,0)的高分辨振转谱,得到其转动常数B’79-81分别为0.08832和0.08805cm^-^1,并提出此系列的角动量量子数Ω应为1。 相似文献
19.
Foltynowicz RJ Robinson JD Zückerman EJ Hedderich HG Grant ER 《Journal of Molecular Spectroscopy》2000,199(2):147-157
Analyses of high Rydberg series of HCO converging to the (030) vibrational state of the cation establish rovibrational state-detailed thresholds for HCO(+). UV-visible laser double resonance isolates series for assignment. Strongly vertical Rydberg-Rydberg transitions from photoselected N' = 0 and N' = 2 rotational levels of the Sigma(-) Renner-Teller vibronic component of the 3ppi (2)Pi (030) complex define individual series converging to rotational levels, N(+) = 1 through 5 and 3 through 5 of the HCO(+) vibrational states (03(1)0) and (03(3)0), respectively. Extrapolation of autoionizing series locates the positions of these rovibrational states to within +/-0.01 cm(-1). The use of this information combined with precise ionization limits for lower vibrational states determined from earlier Rydberg extrapolations and spectroscopic information available from infrared absorption measurements enables an estimate of the force-field parameters for HCO(+) bending. These parameters include the harmonic bending frequency, omega(2) = 842.57 cm(-1), the vibrational angular momentum splitting constant, g(22) = 3.26 cm(-1), and the diagonal bending anharmonicity, x(22) = -2.53 cm(-1), separated from the off-diagonal contribution, x(12), by reference to ab initio calculations. Results of experiment on the higher vibrationally excited states of HCO(+) are compared with recent theoretical predictions. Copyright 2000 Academic Press. 相似文献
20.
I. D. Petsalakis 《Molecular physics》2013,111(4):333-342
Ab initio multireference configuration interaction calculations have been carried out on the lower-lying electronic states of BH and their nonadiabatic interactions. The ab initio data have been included in subsequent calculations involving solution of the complex eigenvalue Schrödinger equation to determine predissociation widths and lifetimes of vibrational-rotational levels of these states. Secondly, previously calculated ab initio data on the Rydberg states and their nonadiabatic interactions have been included in multi-state vibrational calculations on the 3p and 3d complexes in BH and BD. The results are in good agreement with the experimental analysis of the 3p and 3d spectra in BH and BD. Furthermore, interaction of the 3d states with the neighbouring 4s state is also found to be important. 相似文献