Synthesis and spectroscopic characterization of polymer and oligomers of ortho-phenylenediamine

Poly(ortho-phenylenediamine) and oligomers of ortho-phenylenediamine were chemically synthesized and characterized by UV-vis, ¹H and ¹³C NMR, FTIR and resonance Raman spectroscopies. Polymerization of ortho-phenylenediamine in HCl medium with ammonium persulfate only leads the trimer compound, in disagreement with some previous reports. Nevertheless, in acetic acid medium it was possible to prepare a polymer constituted by ladder phenazinic segments with different protonation levels and quinonediimine rings (polyaniline-like). X-ray absorption at N K-edge (N K XANES), X-ray photoelectron (XPS) and Electron paramagnetic resonance (EPR) spectroscopies were used to determine the different kinds of nitrogen presents in this class of polymer. N K XANES spectrum of poly(ortho-phenylenediamine) shows the band of N nitrogen of non-protonated phenazinic rings at 398.2 eV. In addition, XPS and N K XANES data confirm the presence of different types of protonated nitrogens in the polymeric poly(ortho-phenylenediamine) chain and the EPR spectrum shows that the polymer has a very weak polaronic signal.     

时间分辨拉曼光谱研究一氧化氮与肌红蛋白的结合过程

纳秒瞬态拉曼光谱技术是研究分子结构变化超快动态过程的重要实验手段之一.而肌红蛋白(Mb)与小分子配体的结合过程一直是人们研究的焦点.本文旨在利用纳秒瞬态拉曼光谱技术研究小分子配体NO与肌红蛋白结合的动力学过程.通过考察MbNO光解后产物脱氧肌红蛋白(DeoxyMb)与反应物MbNO的ν4特征振动峰的强度比值随激光激发功率的变化,阐述了利用纳秒瞬态拉曼光谱技术研究MbNO体系中NO与DeoxyMb结合过程的可行性.利用纳秒瞬态拉曼光谱技术,获得了与皮秒时间分辨拉曼和皮秒时间分辨吸收相一致的结合动力学实验结果.为研究其它复杂体系的超快结合动力学过程提供了一种新的思路.     

A2( MoO4)3(A=Al,Cr,Fe)结构与相变的Raman光谱研究

用XRD、Raman光谱和DSC研究了Al2 (MoO4)3、Cr2( MoO4)3和Fe2 (MoO4)3的结构与相变.Al2(MoO4)3、Cr2 (MoO4)3和Fe2 (MoO4)3在室温下为单斜相,分别在483 K、673 K和783 K附近转变为正交相.发现MO4四面体的对称和反对称伸缩振动模的频率和相对强...     

高温高压固态复分解反应法生长氮化镓的应变性质研究

本文采用高温高压下固态复分解反应法生长氮化镓.用X射线衍射仪、扫描电子显微镜、激光拉曼光谱仪对其进行分析,结果表明生成了六角纤锌矿结构的氮化镓晶体.该样品在宏观上受到了张应力的作用,退火后,宏观的应变状态由张应变向压应变转变;晶体微观应力减小,晶粒尺寸变大,晶体质量变好.     

快速烧结合成Zr1-xMxW2O8(M=Hf,Sn,Y)固溶体的Raman光谱研究

首次采用快速烧结合成技术制备了Zr1-xMxW2O8 (M=Hf,Sn,Y)系列固溶体.制备的合适条件为:温度1523～1553 K,时间30 min～1 h,同传统固相反应烧结相比,该方法合成时间和能耗显著降低.XRD和Raman光谱分析表明,Zr1-xMxW2O8 (M=Hf,Sn,Y)固溶体具有α-ZrW2O8的...     

3,4-二氯-1,2,5-噻二唑的结构及其振动光谱

实验测量了3,4-二氯-1,2,5-噻二唑分子4000～400 cm-1区域内的红外光谱和3700～100 cm-1范围内的拉曼光谱,使用密度泛函理论计算了分子的稳定结构和振动频率.以实验测定频率为标准采用简正振动分析方法得到了各振动谱带的总能量分布,从而对该分子的振动频率做出了全面归属.     

激发态H2(X1∑+g,v=1,J=1)之间的碰撞能量合并

受激拉曼激发H2(0,1)基态的Q支得到H2(1,1)能级.在室温条件下,利用反斯托克斯拉曼散射(CARS)探测技术测量了碰撞能量合并(EP)过程H2(1,1)+H2(1,1)→H2(2,J)+H2(0,J″)及H2(1,1)与H2(1,J)转动能级间的碰撞转移速率系数.扫描CARS谱表明在H2(1,1)能级的碰撞能量...     

状态转变增强拉曼光谱

表面增强拉曼散射(SERS)是公认的超灵敏的光谱工具.和传统的优化SERS基底材料或构筑完美的结构策略相比,我们提出了一种极其简单和灵敏的方法,该方法被命名为状态转变增强拉曼光谱(STERS).这种STERS检测方法可广泛的应用于毒品安全检测、食品安全和环境保护等方面.如果我们把这种方法和便携式拉曼光谱仪结合,这种应用...     

几种环状分子的拉曼光谱研究

通过实际检测获得了环己烷、四氢呋喃、1,4-二氧己环（二恶烷）几种环状分子的拉曼光谱。并应用密度泛函理论对几种环状分子的拉曼振动峰进行了详细的分析。研究结果表明：几种环状分子最强拉曼振动峰均由环呼吸运动引起,但它们的波数值差异较大,可以作为鉴定此类分子的判断依据。应用拉曼光谱检测技术可以对此类有毒物质进行快速的鉴定与分析。     

Gas-phase Raman spectra of hot bands of fundamentals and combinations associated with the torsional vibration of s-trans-1,3-butadiene and its deuterated isotopologues

The gas-phase Raman spectra of 1,3-butadiene and its 2,3-d₂, 1,1,4,4-d₄, and d₆ isotopologues have been recorded with high sensitivity and resolution of 0.7 cm⁻¹. Hot band series of fundamentals and combinations involving the ν₁₃ torsional vibration of the s-trans rotamer have been observed for each of the isotopologues. Modes studied were ν₁₀ (CH wag), ν₁₂ (CH₂ twist), ν₁₀ + ν₁₂, ν₁₅ (CH₂ wag) + ν₁₆ (CH₂ twist), and ν₂₃ (CH₂ rock) + ν₂₄ (CCC deformation). The spacings of the quantum states of the torsional contribution were found to decrease with additional excitation of this mode (ν₁₃) in the upper vibrational states except for the ν₂₃ + ν₂₄ combination state.