Infrared and near infrared emission spectra of SbH and SbD

The X³Σ⁻ ground state vibration-rotation spectrum of SbH and the near infrared spectra of the b¹Σ⁺-X³Σ⁻ transitions of SbH and SbD have been measured at high resolution by Fourier transform spectroscopy. The SbH and SbD radicals were generated in a tube furnace with a D.C. discharge of a flowing mixture of argon, hydrogen (or deuterium), and antimony vapor. In the infrared region, the 1-0 and 2-1 bands of the three components (0⁺, 1_e, and 1_f) as well as the 0⁺ component of the 3-2 band were observed for ¹²¹SbH and ¹²³SbH. In the near infrared region, the 0-0, 1-1, and 2-2 bands of the b¹Σ⁺-X³Σ⁻ system of both SbH and SbD as well as the 3-3 band of SbD were observed. Except for a few lines, the antimony isotopic shift was not resolved for these electronic spectra. The present data set was combined with the available ground state data on SbD and a¹Δ data for SbH and SbD from previous work, and a least-squares fit was performed for each of the four isotopologues: ¹²¹SbH, ¹²³SbH, ¹²¹SbD, and ¹²³SbD. Improved spectroscopic constants were obtained for the observed vibrational levels of the X³Σ⁻, a¹Δ, and b¹Σ⁺ states of these four isotopologues. In addition, all the above data were also fitted simultaneously to a multi-isotopologue Dunham model, which yielded Dunham constants and Born-Oppenheimer breakdown parameters for these three electronic states. Interestingly, we found that Born-Oppenheimer breakdown corrections were also required for some of the spin-spin and spin-rotation parameters of the X³Σ⁻ state.     

Infrared absorption spectra of 2,3- and 3,5-dichloroaniline

The infrared absorption spectra of 2,3- and 3,5-dichloroanilines have been recorded in the region 250–4000 cm⁻¹. The spectra of the latter are recorded in solid phase (KBr and Nujol mull) and in CS₂/CCl₄ and CHCl₃ solutions while that of the former in thin film only. The spectra have been analysed assuming C ₃ and C_2v point group symmetry respectively and a tentative assignment of the observed bands to different fundamental modes has been made.     

Temperature dependence of infrared reflectance spectra of InN

To investigate both the optical and electrical properties of InN, we have measured the infrared reflectance spectra of InN thin films and performed the fitting analyses of the infrared spectra to obtain not only phonon frequencies and the damping factors but also the carrier concentration of InN. In this paper, we extend the aim of those analyses to the electron mobility and demonstrate that the temperature dependence of the electron mobility can be discussed using the infrared reflectance spectra analyses.     

Fourier transform infrared emission spectra of MnH and MnD

Fourier transform infrared emission spectra of MnH and MnD were observed in the ground X⁷Σ⁺ electronic state. The vibration-rotation bands from v = 1 → 0 to v = 3 → 2 for MnH and from v = 1 → 0 to v = 4 → 3 for MnD were recorded at an instrumental resolution of 0.0085 cm⁻¹. Spectroscopic constants were determined for each vibrational level and equilibrium constants were found from a Dunham-type fit. The equilibrium vibrational constant (ω_e) for MnH was found to be 1546.84518(65) cm⁻¹, the equilibrium rotational constant (B_e) is 5.6856789(103) cm⁻¹ and the eqilibrium bond distance (r_e) was determined to be 1.7308601(47) Å.     

Infrared spectra and transport properties of Li-doped La214 system

The microstructure, charge transport and phonon vibration of polycrystalline samples of Li-doped La214 system have been studied by X-ray diffraction, resistivity and transmission infrared (IR) spectra. It is found that the doping of Li in La₂Cu_1−xLi_xO_y (0x0.5) and La_1.85+xSr_0.15−xCu_1−xLi_xO_y shows different effects on the crystal structure and resistivity. The change of resistivity with Li doping can be interpreted based on the variation of carrier concentration and impurity scattering. The shift of two IR vibration modes around 512 and 683 cm⁻¹, which are referred to the vibrations of apical oxygen and planar oxygen, is analyzed in detail. The change of the intensity for the mode around 683 cm⁻¹ is interpreted in terms of the screened effect of charge carrier in CuO₂ plane. The relation among crystal microstructure, carrier concentration, transport properties and phonon vibration is analyzed and discussed based on the experiment results.     

阿比特龙的红外光谱与前线轨道

采用密度泛函理论的B3LYP混合泛函和6-311G(d,p)基组,通过几何结构优化得到了阿比特龙分子的稳定构型.计算了阿比特龙分子的红外吸收光谱,并与文献数据进行比较,将2971.01、1588.31、1536.13、1450.40、1112.13和1074.44 cm~(-1)等处吸收峰指认为特征吸收峰.在优化计算的基础上,结合Multiwfn软件分析了阿比特龙分子的前线轨道成分,得出阿比特龙分子的亲核能力明显强于其亲电能力,C55、O54原子在95αHOMO中占据的权重分别为61.79%和17.05%,C=O-H部位是其亲核反应的活性中心.研究结果对阿比特龙分子的检测、活性应用等方面具有一定的理论指导意义.     

等离子体X射线吸收谱及发射谱研究

 报道计算高温高密等离子体吸收谱和发射谱（光学薄）的理论方法；该方法基于相对论原子理论，可以计算任何单元素以及多元素等离子体的谱分辨X射线吸收谱和发射谱（光学薄）；应用了量子亏损理论，可以减少计算量。利用该方法计算金等离子体LTE吸收谱，计算结果与实验符合良好。本文还对金等离子体LTE的光学薄发射谱进行了研究, 这将有利于对实验进行进一步的诊断分析。该理论计算方法还可提供等离子体内各电离度能级布居等重要物理参数。因此经“标准实验”检验的该理论计算方法将是提供ICF“精密”物理辐射参数的重要基础。     

等离子体X射线吸收谱及发射谱研究

报道计算高温高密等离子体吸收谱和发射谱（光学薄）的理论方法;该方法基于相对论原子理论,可以计算任何单元素以及多元素等离子体的谱分辨X射线吸收谱和发射谱（光学薄）;应用了量子亏损理论,可以减少计算量。利用该方法计算金等离子体LTE吸收谱,计算结果与实验符合良好。本文还对金等离子体LTE的光学薄发射谱进行了研究, 这将有利于对实验进行进一步的诊断分析。该理论计算方法还可提供等离子体内各电离度能级布居等重要物理参数。因此经“标准实验”检验的该理论计算方法将是提供ICF“精密”物理辐射参数的重要基础。     

大气汽溶胶复合微粒子的光学截面及红外发射率光谱的计算

在文章[1]的基础上,根据M.L.Aden和A.Kerker的复合微粒子光散射理论计算了汽溶胶大气中复合微粒子模型的光学特性,得到了汽溶胶的散射截面、吸收截面和消光截面以及红外发射率光谱,为研究大气红外传输提供了计算方法.     

大气汽溶胶微粒子光学截面及红外发射率光谱的计算

根据Mie微粒子光散射理论计算了汽溶胶大气模型的光学特性,得到了汽溶胶的散射截面、吸收截面和消光截面以及红外波段散射强度分布,同时计算了汽溶胶大气的发射率光谱.为研究大气红外传输提供了计算方法.     

Raman and infrared spectra of tere-phthalaldehyde

The laser Raman spectrum of tere-phthalaldehyde powder has been recorded on a Jobin Yvonhg 2S spectrophotometer with a~100 mW Argon-Ion laser. The infrared spectrum of the solid substance has been recorded on a Perkin-Elmer 621 spectrophotometer in the region 300–4000 cm^-1 using KBr and nujol mull techniques. The observed frequencies have been assigned in terms of the fundamentals, overtones and combinations assumingD _2h point-group symmetry.     

可溶性与不可溶性聚苯胺的红外与Raman光谱研究(英文)

本文比较了可溶性与不可溶性聚苯胺的红外吸收光谱与 Raman 光谱,表明两种聚苯胺在结构上有明显差别。可溶性聚苯胺的主要红外特征峰频率向高频方向移动,吸收带变窄,肩峰清晰可辨。对应于醌基团振动的1595cm~(-1)谱线相对于苯基团振动的1499cm~(-1)谱线强度减弱,1300cm~(-1)谱峰消失。表明可溶性聚苯胺中醌结构单元的数量少,而且含有偶氮基团 N=N 伸缩振动的特征吸收峰1450cm~(-1)。比较两者的 Raman 光谱也给出了相同的结果。可溶性聚苯胺中相对于氧化单元中醌结构的特征峰1566cm~(-1)谱线比相对于还原单元中苯结构的特征峰1620cm~(-1)谱线强度弱得多,也表明可溶性聚苯胺比不可溶性聚苯胺含有较少的醌结构。根据聚苯胺导电机制的质子化模型,由红外与Raman 光谱中相应谱的相对强度的差别可以估计,可溶性聚苯胺具有氧化型与还原型交替结构,质子化程度较低,仅约15%,因此电导率显著下降。     

玉米品种近红外光谱的DFT特征分析方法

提出了一种基于离散傅里叶变换(discrete Fourier transform,DFT)的玉米品种特征分析新方法.实验数据为37个玉米晶种种子的近红外漫反射光谱数据,波段范围为4 000～12 000 cm-1.文中通过对原始数据进行分析,发现扫描频率较高的部分噪声也比较大.文中首先定义了一种类间、类内差异度Qm的...     

Ground state parameters of BiH3 from infrared and millimeter-wave spectra: ground state and equilibrium structures

Unstable, short-lived BiH₃ has been synthesized and investigated by rotational spectroscopy in the range 158 (J=1-0) to 1280 GHz (J=8-7). Quadrupole and spin-rotation hyperfine structures (eQq=584.676(96) MHz), and the A₁A₂ splitting of the K=3 ground state level, have been resolved. By merging the pure rotational data with 1764 ground state combination differences obtained from the analysis of high resolution Fourier transform infrared spectra of the ν₁-ν₄ bands [J. Mol. Spectrosc. (2004) (in press)] spanning J and K values up to 16 and 14, respectively, with 0?ΔK?9, the ground state rotational and centrifugal distortion constants up to octic and sextic terms for reductions A and B, respectively, have been determined. Of the reductions of the ground state rovibrational Hamiltonian, reduction B including ε rather than h₃ as off-diagonal element is clearly favored. An experimental r₀ structure of the very-near spherical oblate symmetric top BiH₃, r(BiH)=178.82 pm and α(HBiH)=90.320°, has been deduced from the rotational constants B₀=2.64160172(18) and C₀=2.6010403(31) cm⁻¹. The derived experimental r_e structure, r_e(BiH)=177.834(50) pm and α_e(HBiH)=90.321(10)°, was determined. This is in excellent agreement with the most recent ab initio structure, r_e(BiH)=177.84 pm, and α_e(HBiH)=90.12°.     

High-resolution infrared spectra of NCCN and NCCN

High-resolution spectra of ¹⁵N¹²C¹²C¹⁵N and ¹⁴N¹³C¹³C¹⁴N have been measured and analyzed from 200 to 3600 cm⁻¹. All the vibrational levels below 900 cm⁻¹ have been observed and characterized. The Fermi resonance between ν₂ and 2ν₄ has been studied and the resonance constant has been determined for several cases. Several Σ⁻ states have been directly observed for the first time for each isotopomer, the (0001111)0f, (0011111)0f, and (0002222)0f states. The pattern of the energy levels for clusters of l-type resonance coupled levels, such as 0001131,3, has been determined for cyanogen for the first time. Among other things this involved the determination of the vibrational l-type resonance constant, r₄₅. Many of the power series constants, α_i and x_ij, and higher order constants have been determined.     

An Infrared Study of Conformational Isomerism in Cyclohexyl Iodide

Abstract

A comprehensive solvent, concentration, and temperature study has been made of the 850 to 400 cm^?1 region of the infrared spectrum of cyclohexyl iodide. This causes us to reject the assignment of Larnaudie and of Chiurdoglu and Reisse of v(C-I)_eq at 654 cm^?1 and v(C-I)^ax at 638 cm^?1, and to suggest that the two modes are almost coincident in n-hexane solution at 656.2 cm^?1 (eq) and 655.6 cm^?1 (ax).     

Photocurrent spectra for above and below bandgap energies from photovoltaic PbS infrared detectors with graphene transparent electrodes

We discussed photocurrent spectra of photovoltaic PbS infrared detectors using multi-layer graphene as transparent electrode, where p-PbS films were deposited on TiO₂/FTO substrates by chemical bath deposition. In the photocurrent spectra, we observed both above-bandgap and sub-bandgap photocurrent without any external bias. We discussed impurity band model and grain boundary model in order to explain the sub-bandgap photocurrent near 15 μm. Since FTO is transparent in the visible range, we were able to illuminate green laser beam from the FTO back-side, and photo-response up to 50 μm was found to be enhanced. This long wavelength photo-response was attributed to the excitation of the photo-electrons accumulated at the TiO₂/PbS interface. Our photovoltaic PbS devices can detect not only short-infrared but also terahertz radiation at room temperature, which is highly applicable to various fields.     

有机硼酸盐插层Zn/Al-LDH的红外和拉曼光谱特征

研究了碳酸根和硼酸根的二元锌铝水滑石的X射线衍射,拉曼和红外光谱特征。采用一步水热共沉淀法,分别制得结晶良好的层间为碳酸根和硼酸根的二元锌铝水滑石。X射线衍射分析显示,硼酸根插层后水滑石（003）特征衍射峰向小角度移动,峰型尖锐,水滑石通道高度从0.28 nm增加至0.42 nm;红外光谱和拉曼光谱特征表明,硼酸根插层后,碳酸根的红外和拉曼特征峰消失。层间硼酸根以B₃O₃(OH)-₄,B₄O₅(OH)2-₄和B(OH)-₄三种形式存在。随层间离子的不同,与羟基相关的红外光谱和拉曼光谱峰位均有所改变。研究结果表明以硼酸三正丁酯为插层剂,可获得单一相、纯度较高的硼酸根型锌铝水滑石,拉曼光谱可准确探测水滑石层间阴离子变化对其结构和性能的影响。