Energy partitioning in two kinds of NO molecules generated from the reaction of O(1D) with N2O: Vibrational state distributions of “new” and “old” NO’s
摘要:
The reaction of O(1D) with N2O produces two kinds of NO molecules, the “old” one which originally exists in N2O and the “new” one which includes the attacking O atom. Using the isotopically labeled reagent, we determined the vibrational state distributions of these NO’s (X 2Π; v=0–17) separately. To obtain the distributions, two types of experiments were performed with the laser-induced fluorescence (LIF) technique via the NO A←X and B←X transitions. First, the relative populations of NO molecules (the sum of the two kinds of NO’s) in v=0–11 levels were measured with unlabeled reagents. Then, isotopically labeled reaction, O18(D1)+N216O→N18O+N16O, was utilized to determine the relative ratio between the two kinds of NO’s in the vibrational levels of v=0–5 and 12–15. Combining the above results with previously determined vibrational state distribution of NO in high vibrational levels (v=11–17) [J. Chem. Soc., Faraday Trans. 94, 1575 (1998)], we were able to obtain a complete set of vibrational state distributions. It was found that the old NO dominantly populated in v=0 and 1 whereas the new NO extended its population toward higher vibrational levels (v=4–15). However, in high vibrational levels, the old NO still have a considerable population due to the rapid energy transfer to the old NO. The observed efficient energy transfer to the old NO is attributed to the absence of light atoms in the present reacting system. Compared with the system including hydrogen atoms, the state density and the momentum coupling among the vibrational modes are much larger and accelerate the energy redistribution in spite of the short lifetime.
结合了693 nm激光照射和红外吸收光谱技术,在10 K的天然氧气基质中研究了可见光区域中18 O 3(完全取代的臭氧或888)的光解离。臭氧888被转化为(不对称和对称的)668和686种,它们通过将18 O与16交换而进一步转化为正常的666种。O原子。888的整体光解离是一阶过程,并提出了一个合理简单的模型,该模型可以令人满意地重现观察到的动力学结果。光解动力学速率常数的值表明可见光带的吸收截面相对于气相中的吸收截面有所增加。实验表明,在18 O氧原子与基质16 O 2分子重组期间,相对于对称物种686,不对称668物种的形成速率增加。
Isomers of OCS[sub 2]: IR absorption spectra of OSCS and O(CS[sub 2]) in solid Ar
作者:Wen-Jui Lo、Hui-Fen Chen、Po-Han Chou、Yuan-Pern Lee
DOI:10.1063/1.1822919
日期:——
quantum-chemical calculations. These calculations using density-functional theory (B3LYP/aug-cc-pVTZ) predict four stable isomers of OCS(2): O(CS(2)), SSCO, OSCS, and SOCS, listed in order of increasing energy. According to calculations, O(CS(2)) has a cyclic CS(2) moiety and is the most stable isomer of OCS(2). OSCS is planar, with bond angles angle OSC congruent with 111.9 degrees and angle SCS congruent with
Investigation of the Thermal and Photochemical Reactions of Ozone with 2,3-Dimethyl-2-butene
作者:Bridgett E. Coleman、Bruce S. Ault
DOI:10.1021/jp108457w
日期:2010.12.9
The matrixisolation technique, combined with infrared spectroscopy and twin jet codeposition, has been used to characterize intermediates formed during the ozonolysis of 2,3-dimethyl-2-butene (DMB). Absorptions of early intermediates in the twin jet experiments grew up to 200% upon annealing to 35 K. A number of these absorptions have been assigned to the elusive Criegee intermediate (CI) and secondary
The Synthesis of <sup>15</sup>N- and <sup>18</sup>O-Isotopically-Enriched Nitryl Bromide, IR Matrix Spectra, and Force Fields of BrNO<sub>2</sub>, <i>cis-</i>BrONO, and <i>trans-</i>BrONO
作者:Dieter Scheffler、Helge Willner
DOI:10.1021/ic9803006
日期:1998.9.1
scrambling in the reaction between BrNO and (18)O(3) as well as in the gas phase equilibrium BrNO + NO(2) right harpoon over left harpoon BrNO(2) + NO are investigated. For the equilibrium constant a lower limit of K(298) >/= 1 x 10(-)(3) is deduced from infrared measurements. A detailed IR and Raman study on BrNO(2) is performed. Photolysis of matrix-isolated BrNO(2) at different wavelengths leads to a
BrNO和O(3)在低压下(<10 mbar)之间的气相反应导致以约60%的收率形成BrNO(2)。以这种方式制备了(15)N-和(18)O-标记的BrNO(2)。另外,还表明,BrNO(2)也是通过在气态BrNO与掺杂有H(2)O(2)的固体硫酸之间进行的异质低温反应而形成的。可以假设在平流层条件下可以类似的方式形成BrNO(2)。研究了在BrNO与(18)O(3)之间的反应以及在气相平衡中的BrNO + NO(2)右鱼叉在左鱼叉BrNO(2)+ NO上的同位素加扰。对于平衡常数,从红外测量值推导出K(298)> / = 1 x 10(-)(3)的下限。对BrNO(2)进行了详细的IR和拉曼研究。基质分离的BrNO(2)在不同波长下的光解导致顺式和反式BrONO的混合物。BrNO(2)(6个基本原理,7个组合),顺式BrONO(5个基本原理,1个泛音)和反式BrONO(4个基本原理,8个
A Study of the Products of the Reaction of Phosphorus and Dioxygen
作者:Charles W. Bauschlicher、Mingfei Zhou、Lester Andrews
DOI:10.1021/jp993623b
日期:2000.4.1
The products of the reaction of laser-ablated red phosphorus and dioxygen have been studied using experiment and theory. The bands at 480.3 and 1273.3 cm-l, previously attributed to PO3 in the matrix isolation IR experiments, are reassigned to PO3-. Also observed in experiment are PO2, PO2-, P2O, OPOPO, P4, and higher oxides.
Conversion of SO<sub>2</sub> to SO<sub>3</sub> by In Situ Photolysis of SO<sub>2</sub> and O<sub>3</sub> Mixtures Isolated in Argon Matrixes: Isotopic Effects
作者:H. Chaabouni、L. Schriver-Mazzuoli、A. Schriver
DOI:10.1021/jp993164e
日期:2000.4.1
investigated at low temperature in an argon matrix. Formation of stable SO3 occurs from the reaction between SO2 and O(1D) and also by oxygen atom transfer within the SO2:O3 complex. Use of isotopic SO2 species led to unusual observations suggesting that photooxidation of SO2 proceeds via an intermediate species, namely, OSOO; this trioxide sulfur isomer transforms into SO3 by tunneling. In the gas phase