Spectroscopic analysis of asymmetric top free radicals——Application to pure rotational spectra of NO_2 in the ground vibronic state

Several key problems involved in the analyses of spectra of asymmetric top molecules, i.e., the effective Hamiltonian, the representation and basis vector, identification of energy levels, the selection rules, the relative intensity, and Zeeman tuning rate, were elucidated systematically. Introducing the high-order centrifugal distortion terms into the effective Hamiltonian, the precision for calculation has been improved substantially, which allows us to analyze the high-lying rotational transitions. A global analysis of all available spectra of 14N16O2 in the ground vibronic state has been made to obtain a set of molecular constants of 14N16O2 in the ground vibronic state which is the most precise and extensive so far. Using the improved parameters, some FIR LMR lines left unassigned hitherto have been identified successfully.     

CF X^2П（ν=1）远红外及NO X^2П（ν←0）中红外激光磁共振光谱的标识

根据塞曼效应理论和浙江磁共振（LMR）光谱原理,本文建立一了套用于标识激光磁共振光谱的模型方法,并成功地对CF X^2П（ν=1）远红外及NO X^2П（ν←0）中红外激光磁共振光谱进行了标识。为新自由基分子的激光磁共振光谱提供了快速而准确的方法。     

Analysis of the hyperfine structures and A doubling of high-resolution LMR spectra of ~(15)N~(16)O (X~2Π)

From the theories of the nuclear hyperfine structure (HFS) and A doubling of diatomic molecules, several brief algebraic equations for interpretation of HFS and A doubling of transitions of diatomic molecule have been developed. A few important parameters of HFS and A doubling of 15N16O have been efficiently and accurately obtained from the analysis of the high resolution spectra of 15N16O (X2Π) observed in our experiments with these equations. This method can provide an effective approach to obtain important hyperfine parameters of novel radicals from their high resolution laser magnetic resonance spectra.     

14N16O2ν3带中红外激光磁共振超精细结构谱

报道了14N16O2ν3带(001-000)的5组新的超高分辨激光磁共振谱线的观测,包括实验的背景、装置、方法和结果.由于利用了内腔饱和吸收情况下的兰姆凹陷和最优化的相敏调制探测技术,所得光谱的分辨率达到了微波谱量级.这些谱线是分析14N16O2乃至非对称陀螺自由基分子的塞曼效应和超精细结构特性的重要实验资料.     

NO(X2Π1/2,3/2)υ=1←0塞曼跃迁谱及其特性研究

根据塞曼效应理论和激光磁共振光谱技术(LMR)的基本原理,讨论了双原子分子2П态的塞曼效应特性并导出了解释分子塞曼跃迁的简明代数拟合方程,用这些方程对14N16O(X2Π1/2,3/2)及15N16O(X2Π3/2) (υ=1←0)的LMR谱线进行数据拟合,得到塞曼跃迁上、下子能级的gJ因子值和二级塞曼效应因子k2.将按Hund耦合情形(a)及过渡情形(ab)的理论和拟合方程计算出的磁场位置分别与实验结果相比较,结果表明对NO分子而言,过渡情形(ab)能较真实反映它的耦合情况,且在较高强度磁场下,必须计及二级塞曼修正.验证了采用上述代数拟合方程实现新分子LMR谱线标识和指认的可靠性,并提供了系统的处理方法.     

非对称陀螺自由基分子光谱的标识分析──NO_2基振动态纯转动光谱分析

系统阐述了非对称陀螺分子光谱的标识分析工作涉及的一些关键理论问题, 包括有效Hamilton量、表象和基矢、能级识别、跃迁选择规则、相对强度和Zeeman调制率等, 并在有效Hamilton量中引入高阶离心畸变项, 大大提高了计算精度, 并使高转动量子数跃迁的标识分析成为可能. 作为应用实例, 对14N16O2基振动态的零场和磁共振谱进行了统一分析(global analysis), 获得了迄今为止最精确、最完整的14N16O2基振动态分子结构参数, 并对Curl和Brown等人过去未能标识的14N16O2高转动量子数跃迁远红外激光磁共振谱线进行了成功标识.     

CO LMR spectrum of ~(14)N~(16)O and its analysis with spectra of ~(14)N~(17)O and ~(14)N~(18)O

LMR spectra for v=1←0 transitions of 14N16O in X2Π1/2,3/2 states were observed at 5.6 μm and 5.4 μm of CO laser. Introducing the advanced isotopic molecular constant scaling function to Hund's case (a) diatomic structure model, these spectra were analyzed and fitted together with all reliable previous spectral data of 14N16O as well as 14N17O and 14N18O. A full set of precise molecular parameters and their vibrational dependencies have been determined with much higher precision (1 -2 orders for most parameters). Many of them have been obtained for the first time. Using isotopic scaling function, the molecular constants of 14N17O and 14N18O were deduced.     

THE MID-INFRARED FREQUENCY STANDARD USING 14NmO(m=16,17,18) SPECTRAL LINES

Based on the global analysis of all available and reliable data for isotopic species ¹⁴N^mO(m=16,17,18), the ¹⁴N¹⁶O rovibrational spectral lines are calculated with very high accuracy and completely agree with previous results. These lines with relative intensities can be achieved as an infrared frequency standard in the spectral range 1600-5600 cm^-1. The calculated rovibrational transitions of ¹⁴N^mO(m=17,18) have the same accuracy as that for ¹⁴N¹⁶O although their data are rare due to their small natural abundance.     

速度调制光谱技术特性的研究

利用N2^ A^2Ⅱu-X^2∑g^ (2-0)Meinel带系谱线研究了速度调制光谱技术的特性。从理论和实验上考察了速度调制谱信号强度与放电电流、放电气体的气压以及真空泵的泵速的关系。利用所获得的研究结果提高谱仪的灵敏度和分辨率达3倍以上,实验运行开支节省3／4左右。表明该实验研究具有重要的应用价值。     

CF X2Π（υ＝1）远红外及NO X2Π（υ＝1←0）中红外激光磁共振光谱的标识

根据塞曼效应理论和激光磁共振 (LMR)光谱原理 ,本文建立了一套用于标识激光磁共振光谱的模型方法 ,并成功地对CFX2 Π(υ =1)远红外及NOX2 Π(υ =1← 0 )中红外激光磁共振光谱进行了标识。为新自由基分子的激光磁共振光谱提供了快速而准确的标识方法