氯乙烯的同步幅射光电离及C-H和C-CI键离解能的测定

利用同步辐射对C~2H~2CI进行了光电研究,得到了电离势IP(C~2H~2CI)为10.03±0.01eV及其碎片的光电离出现势,导出了离解能D~0(C~2H~2CI-H),D~0(C~2H~2CI^+-H),D~0(C~2H~2CI-H^+),D~0(C~2H~2-CI)和D~0(C~2H~3^+-CI),它们的值分别为5.09±0.05,5.02±0.08,8.66±0.05,3.64±0.10和2.56±0.05eV.     

钌铁双核配合物的合成及猝灭[Ru(bpy)~3]^2^+发光过程研究

合成了含二氮芴和联吡啶等配体的一系列新型钌铁双核配合物:[(C~1~0H~6N~2)C=N-N=CR-Fc)Ru(bpy)~2]·(PF~6)~2,[(C~1~0H~6N~2)C=N--C~6H~4-N=CR-Fc)Ru(bpy)~2]·(PF~6)~2,[(C~1~0H~6N~2)C=N-C~6H~4-C~6H~4-N=CR-Fc)Ru(bpy)~2]·(PF~6)~2,并对其进行了光谱表征,通过对该类配合物的循环伏安和发光光谱研究,讨论其激发态的氧化还原性和对[Ru(bpy)~3]^2^+发光过程的猝灭作用.研究表明猝灭过程为扩散控制的双分子交换能量传递     

1，2－二甲氧基乙烷的真空紫外光电离和光解离

利用同步辐射真空紫外光对1，2－二甲氧基乙烷进行光电离解离研究，得到了 该分子的电离势为（9.33±0.04)eV，碎片离子CH_3OCH_2CH_3~+和CH_3OCH_2~+的 出现势分别为(9.83±0.05)eV, (9.99±0.05)eV，根据实验结果和B3LYP／6－31＋ G(d)理论计算的结果，分析了可能的解离通道，并得到了离子生成焓、键解离能这 些重要的热力学数据。     

过渡金属卡宾配合物:VIII. 四羰基[乙氧基(芳基)卡宾]铁配合物的方便合成法

五羰基铁, Fe(CO)~5(1), 与芳基锂(ArLi)在乙醚中于低温下反应, 所生成的酰羰基锂中间体在水溶液中于0℃用 Et~3OBF~4烷基化, 制得六个标题配合物(co)~4Fec(OC~1H~5)Ar(Ar:C~6H~5, 2;o-CH~3C~6H~4,3;p-CH~3C~6H~4, 4;p-CH~3OC~6H~4,5;C~6Cl~5,6;p-CF~3C~6H~4,7). 当用p-CF~3C~6H~4Li作为亲核试剂与1 反应时, 除生成7外, 还获得副产物对三氟甲基苯丙酮,p-CF~3C~6H~4COC~2H~5(8)。     

五氟乙烷的真空紫外光电离光解离

利用同步辐射真空紫外光电离结合飞行时间质谱对五氟乙烷(CHF₂CF₃)进行了光电离光解离的研究，测定了CHF₂CF₃的电离势及该分子主要碎片离子的出现势. 结果表明: CHF₂CF₃的绝热电离势为(12.25±0.10) eV, 主要碎片离子有CF₂CF_{3⁺、CHFCF3⁺、CF2CF2⁺、CF3⁺、CHF2⁺、CHF⁺和CF⁺，其出现势分别为 (13.93±0.10) eV, (15.25±0.10) eV, (15.12±0.10) eV, (13.30±0.05) eV, (13.05±0.08) eV, (19.17±0.10) eV和 (19.56±0.15) eV. 另外，用从头算分子轨道理论计算了解离电离过程中所有碎片的总能量，并给出了电子态及对称性. 根据实验结果和理论计算，分析了可能的解离通道，并得到了分子及母体离子的键解离能等重要的热力学数据.}     

过渡金属卡宾配合物:VIII. 四羰基[乙氧基(芳基)卡宾]铁配合物的方便合成法

五羰基铁, Fe(CO)~5(1), 与芳基锂(ArLi)在乙醚中于低温下反应, 所生成的酰羰基锂中间体在水溶液中于0℃用 Et~3OBF~4烷基化, 制得六个标题配合物(co)~4Fec(OC~1H~5)Ar(Ar:C~6H~5, 2;o-CH~3C~6H~4,3;p-CH~3C~6H~4, 4;p-CH~3OC~6H~4,5;C~6Cl~5,6;p-CF~3C~6H~4,7). 当用p-CF~3C~6H~4Li作为亲核试剂与1 反应时, 除生成7外, 还获得副产物对三氟甲基苯丙酮,p-CF~3C~6H~4COC~2H~5(8)。     

1-甲基-1-乙基-3-丁烯基环戊二烯基稀土二氯化物的 合成与表征

报道了1-甲基-1-乙基-3-丁烯基环戊二烯基稀土二氯化物的合成。用元素分析、质谱、红外光谱和核磁共振表征了这类配合物的组成为[C~5H~4C(CH~3)(C~2H~5)CH~2CH＝CH~2]LnCl~2·MgCl~2·THF[Ln=La(1),Nd(2),Sm(3),Gd(4)]。     

双μ~3-O四核过渡金属簇合物的研究I.[M~2M'~2O~2(C~2H~5COO)~7(bipy)~2]·ClO~4(M=Fe;M'=Fe或Cr族合物的合成和晶体结构

本文采用2,2-联二吡啶与氧心三核物[M~3O(C~2H~5COO)~6(H~2O)~3]·NO~3(M=Fe;Cr)在乙腈中反应的方法制备了两个簇合物:[Fe~4O~2(C~2H~5COO)~7(bipy>~2]·[Fe~2Cr~2(C~2H~5COO)~7(bipy>~2]·ClO~4(2).从测定的单胞参数可确定它们为异质同晶,进而测定了簇合物1的结构.晶体属三斜晶系,空间群PI,单胞参a=1.5328(2),b=1.6325(2),c=1.3017(2)nm,a=113.49(1),β=115.12(1),γ=94.11(1)°;Ⅴ=2.5882nm^3,D~c=1.51g.cm^-3,Z=2,R=0.063,R~w=0.094.     

双μ~3-O四核过渡金属簇合物的研究I.[M~2M'~2O~2(C~2H~5COO)~7(bipy)~2]·ClO~4(M=Fe;M'=Fe或Cr族合物的合成和晶体结构

本文采用2,2-联二吡啶与氧心三核物[M~3O(C~2H~5COO)~6(H~2O)~3]·NO~3(M=Fe;Cr)在乙腈中反应的方法制备了两个簇合物:[Fe~4O~2(C~2H~5COO)~7(bipy>~2]·[Fe~2Cr~2(C~2H~5COO)~7(bipy>~2]·ClO~4(2).从测定的单胞参数可确定它们为异质同晶,进而测定了簇合物1的结构.晶体属三斜晶系,空间群PI,单胞参a=1.5328(2),b=1.6325(2),c=1.3017(2)nm,a=113.49(1),β=115.12(1),γ=94.11(1)°;Ⅴ=2.5882nm^3,D~c=1.51g.cm^-3,Z=2,R=0.063,R~w=0.094.     

富勒烯C~6~0与二茂铁酮亚胺电荷转移相互作用的研究

C~6~0与三种二茂铁酮亚胺η^5-C~5H~5Fe[C~5H~4C(CH~3)=N-C~6H~4R-p]-η^5(1a R=H，1bR=CH~3，1c R=OCH~3)在甲苯和室温下可发生电荷转移相互作用形成三种电荷转移配合物η^5-C~5H~5Fe[C~5H~4C(CH~3)=N-C~6H~4R-p]-η^5/C~6~0 (2a R=H，2b R=CH~3，2c R=OCH~3)。通过紫外光谱证实了它们的存在，并用Benesi-Hildebrand方程求出了2a、2b和2c的电荷转移平衡常数分别为0.769、0.928和2.353mol^-^1·dm^3。鉴于它们远大于普通有机胺与C~6~0形成的电荷转移配合物的平衡常数，因此可认为在2a～2c中存在着由二茂铁核及亚胺基向C~6~0的双重电荷转移相互作用。     

Si(CH3)2Cl2分子的电离电势和化学键能的测定

有机硅化合物是半导体工业中产生硅元件的基本原料和有机合成中的重要试剂，是多年来大家研究较多的分子体系之一．本文报导了用同步辐射加速器产生的真空紫外光，电离St（CH3hCI。分子．在50－120n－m波长范围内，测量了各种离子产物与真空紫外光波长的关系，推算得它的绝热电离电势和离子中几个化学键的键能．1实验装置和方法本工作在国家同步辐射实验室光化学实验站进行．进行分子真空紫外光电离研究的实验系统已在文献山中详细描述．同步辐射加速器产生的真空紫外光波长用Ne气的电离势标定，其误差＜士0－Inln．单色仪的分辨率为河凸…     

溴乙烷光电离解离的理论计算和实验

分子的电离电势、键能和离子的标准生成焓等都是非常重要的物理化学数据,它们对化学反应机理等研究有很大帮助,精确测定离子的出现势,就可以获得这些热力学常数.迄今为止,有关溴乙烷(Ｃ2Ｈ5Ｂｒ)电离解离过程的研究已有若干报导[1-3],但这些结果均是在常温条件下,用电子轰击电离、彭宁电离或真空紫外灯辐照等方法获得的,由于常伴有热带效应、离子分子反应、离子对形成等过程[4],其结果的准确性往往较差.本文首次报导使用同步辐射光源对Ｃ2Ｈ5Ｂｒ进行光电离解离研究.通过准确测量母体离子以及几种主要碎片离子的出现势,结合已有的公认的热力…     

对氨基偶氮苯的同步辐射光电离与光离解

In this paper, the photoionization and photodissociative ionization processes of p-aminoazobenzene (pAAB, C12H11N3) using coincidence technology with vacuum ultraviolet synchrotron radiation (SR) photoionizaton mass spectroscopy are reported. The ionization potential (IP) of this molecule and the appearance potentials (AP) of the important ionic fragments from the SR photodissociative ionization of pAAB have been measured. On the basis of the IP(C12H11N3) and AP measured in this experiment and the IP(C6H5) from the literature, the dissociative energy D 0(C 6H 5-N 2C 6H 4NH 2),D 0(C 6H + 5-N 2C 6H 4NH 2),D 0(C 6H 5-N 2C 6H 4NH + 2),D 0(C 6H 5N 2-C 6H 4NH 2 +) and ionization potential of free radical N 2C 6H 4NH 2 have been evaluated. Based on the results of the mass spectroscopy of pAAB obtained with SR photoionization, the possible channels of photodissociative ionization of pAAB have been analyzed. The processes(molecular ions or the fregmental ions) giving rise to the ions C 6H + 5 and C 6H 6N + need further study.     

对羟基偶氮苯的同步辐射光电离及光离解

偶氮染料分子中含有一个或多个偶氮基 ,是品种最多、应用最广的一类合成染料 ,容易发生感光异构[1 ] ,近年来已引起材料学家对它们的光子模式信息存储能方面的特别关注[2 ] 。我们使用光电离质谱法对偶氮苯类化合物进行了光电离与光离解研究 ,获得了这类物质的一些重要的物理化学数据。本文首次报道用同步辐射光电离质谱法研究对羟基偶氮苯的一些结果 ,给出了它的电离热、主要碎片离子的出现势 ,由此推导出若干个键的离解能。并根据该分子的光电离质谱结果 ,对其光离解通道进行了初步的分析。1　实验部分本工作是在国家同步辐射实验室光化学…     

Si(CH3)3Cl分子电离电势和化学键能的测定

The photoionization spectroscopy of Si(CH3)3Cl in the range of 50 -130 nm was studied with synchrotron radiation source. The adiabatic ionization potentials of molecule Si(CH3)3Cl and radical Si(CH3)3 are 10.06 ±0.02 eV and 7.00±0.03 eV respectively. In addition, the appearance potentials of Si(CH3)2Cl+, Si(CH3)3+, SiCl+ and SiCH3+ were determined:
AP(Si(CH3)2Cl+) ＝10.49±0.02eV, AP(Si(CH3)3+) ＝ 11.91 ±0.02eV
AP(SiCl+) ＝ 18.64 ±0.06eV, AP(SiCH3+)＝ 18.62 ±0.02eV
From these, some chemical bond energies of Si(CH3)3Cl+ were calculated:
D(Si(CH3)2Cl+ - CH3) ＝0.43 ±0.02eV, D(Si(CH3)3+ - Cl) ＝ 1.85 ± 0.02eV
D(SiCH3+ - (2CH3 ＋ Cl)) ＝ 8.56 ± 0．06eV, D(SiCH3+ - 2CH3) ＝6.71±0．06eV
D(SiCl+ - 3CH3) ＝ 8.58 ± 0.06eV, D(SiCl＋- 2CH3) ＝ 8.15 ±0.06eV
D(SiCH3+- (CH3 ＋ Cl)) ＝8.13 ±0.06eV     

Electron ionization of acetylene

Relative partial ionization cross sections and precursor specific relative partial ionization cross sections for fragment ions formed by electron ionization of C2H2 have been measured using time-of-flight mass spectrometry coupled with a 2D ion-ion coincidence technique. We report data for the formation of H+, H+2, C2+, C+/C2+ 2, CH+/C2H+2, CH+2, C+2, and C2H+ relative to the formation of C2H+2, as a function of ionizing electron energy from 30-200 eV. While excellent agreement is found between our data and one set of previously published absolute partial ionization cross sections, some discrepancies exist between the results presented here and two other recent determinations of these absolute partial ionization cross sections. We attribute these differences to the loss of some translationally energetic fragment ions in these earlier studies. Our relative precursor-specific partial ionization cross sections enable us, for the first time, to quantify the contribution to the yield of each fragment ion from single, double, and triple ionization. Analysis shows that at 50 eV double ionization contributes 2% to the total ion yield, increasing to over 10% at an ionizing energy of 100 eV. From our ion-ion coincidence data, we have derived branching ratios for charge separating dissociations of the acetylene dication. Comparison of our data to recent ab initio/RRKM calculations suggest that close to the double ionization potential C2H2+2 dissociates predominantly on the ground triplet potential energy surface (3Sigma*g) with a much smaller contribution from dissociation via the lowest singlet potential energy surface (1Delta g). Measurements of the kinetic energy released in the fragmentation reactions of C2H2+2 have been used to obtain precursor state energies for the formation of product ion pairs, and are shown to be in good agreement with available experimental data and with theory.     

TPEPICO spectroscopy of vinyl chloride and vinyl iodide: neutral and ionic heats of formation and bond energies

The 0 K dissociative ionization onsets of C2H3X --> C2H3(+) + X (X = Cl, I) are measured by threshold photoelectron-photoion coincidence spectroscopy. The heats of formation of C2H3Cl (Delta H(f,0K)(0) = 30.2 +/- 3.2 kJ mol(-1) and Delta(H f,298K)(0) = 22.6 +/- 3.2 kJ mol(-1)) and C2H3I (Delta(H f,0K)(0) = 140.2 +/- 3.2 kJ mol(-1) and Delta(H f,298K)(0) = 131.2 +/- 3.2 kJ mol(-1)) and C- X bond dissociation enthalpies as well as those of their ions are determined. The data help resolve a longstanding discrepancy among experimental values of the vinyl chloride heat of formation, which now agrees with the latest theoretical determination. The reported vinyl iodide heat of formation is the first reliable experimental determination. Additionally, the adiabatic ionization energy of C2H3I (9.32 +/- 0.01 eV) is measured by threshold photoelectron spectroscopy.     

Photoionization of 1-alkenylperoxy and alkylperoxy radicals and a general rule for the stability of their cations

The photoionization of 1-alkenylperoxy radicals, which are peroxy radicals where the OO moiety is bonded to an sp2-hybridized carbon, is studied by experimental and computational methods and compared to the similar alkylperoxy systems. Quantum chemical calculations are presented for the ionization energy and cation stability of several alkenylperoxy radicals. Experimental measurements of 1-cyclopentenylperoxy (1-c-C5H7OO) and propargylperoxy (CH2=C=CHOO) photoionization are presented as examples. These radicals are produced by reaction of an excess of O2 with pulsed-photolytically produced alkenyl radicals. The kinetic behavior of the products confirms the formation of the alkenylperoxy radicals. Electronic structure calculations are employed to give structural parameters and energetics that are used in a Franck-Condon (FC) spectral simulation of the photoionization efficiency (PIE) curves. The calculations also serve to identify the isomeric species probed by the experiment. Adiabatic ionization energies (AIEs) of 1-c-C5H7OO (8.70 +/- 0.05 eV) and CH2=C=CHOO (9.32 +/- 0.05 eV) are derived from fits to the experimental PIE curves. From the fitted FC simulation superimposed on the experimental PIE curves, the splitting between the ground state singlet and excited triplet cation electronic states is also derived for 1-c-C5H7OO (0.76 +/- 0.05 eV) and CH2=C=CHOO (0.80 +/- 0.15 eV). The combination of the AIE(CH2=C=CHOO) and the propargyl heat of formation provides Delta f H(0)(o) (CH2=C=CHOO+) of (1162 +/- 8) kJ mol-1. From Delta f H(0)(o) (CH2=C=CHOO+) and Delta f H (0)(o) (C3H3+) it is also possible to extract the bond energy D(0)(o)(C3H3+-OO) of 19 kJ mol-1 (0.20 eV). Finally, from consideration of the relevant molecular orbitals, the ionization behavior of alkyl- and alkenylperoxy radicals can be generalized with a simple rule: Alkylperoxy radicals dissociatively ionize, with the exception of methylperoxy, whereas alkenylperoxy radicals have stable singlet ground electronic state cations.     

Combined vacuum ultraviolet laser and synchrotron pulsed field ionization study of CH2BrCl

The pulsed field ionization-photoelectron (PFI-PE) spectrum of bromochloromethane (CH2BrCl) in the region of 85,320-88,200 cm-1 has been measured using vacuum ultraviolet laser. The vibrational structure resolved in the PFI-PE spectrum was assigned based on ab initio quantum chemical calculations and Franck-Condon factor predictions. At energies 0-1400 cm-1 above the adiabatic ionization energy (IE) of CH2BrCl, the Br-C-Cl bending vibration progression (nu1+=0-8) of CH2BrCl+ is well resolved and constitutes the major structure in the PFI-PE spectrum, whereas the spectrum at energies 1400-2600 cm-1 above the IE(CH2BrCl) is found to exhibit complex vibrational features, suggesting perturbation by the low lying excited CH2BrCl+(A 2A") state. The assignment of the PFI-PE vibrational bands gives the IE(CH2BrCl)=85,612.4+/-2.0 cm-1 (10.6146+/-0.0003 eV) and the bending frequencies nu1+(a1')=209.7+/-2.0 cm-1 for CH2BrCl+(X2A'). We have also examined the dissociative photoionization process, CH2BrCl+hnu-->CH2Cl++Br+e-, in the energy range of 11.36-11.57 eV using the synchrotron based PFI-PE-photoion coincidence method, yielding the 0 K threshold or appearance energy AE(CH2Cl+)=11.509+/-0.002 eV. Combining the 0 K AE(CH2Cl+) and IE(CH2BrCl) values obtained in this study, together with the known IE(CH2Cl), we have determined the 0 K bond dissociation energies (D0) for CH2Cl+-Br (0.894+/-0.002 eV) and CH2Cl-Br (2.76+/-0.01 eV). We have also performed CCSD(T, full)/complete basis set (CBS) calculations with high-level corrections for the predictions of the IE(CH2BrCl), AE(CH2Cl+), IE(CH2Cl), D0(CH2Cl+-Br), and D0(CH2Cl-Br). The comparison between the theoretical predictions and experimental determinations indicates that the CCSD(T, full)/CBS calculations with high-level corrections are highly reliable with estimated error limits of <17 meV.     

对氨基偶氮苯的同步辐射光电离与光离解

偶氮染料是染料中品种最多、应用最广的一类合成染料,它的分子中含有一个或几个偶氮基(-Ｎ=Ｎ-).偶氮苯类化合物容易发生感光异构现象[1],所以近年来材料科学家对它们的光子模式信息存储性能也特别感兴趣[2].我们使用光电离质谱法对这类分子进行光电离与光离解研究,可以得到这类物质的一些重要物理化学数据.本文首次报导了使用同步辐射光电离质谱法研究对氨基偶氮苯的一些结果.给出了它的电离势、主要碎片离子的出现势,导出了几个键的离解能;并根据该分子的光电离质谱结果,对它的光离解电离通道进行了初步分析.1　实　验由于ｐＡＡＢ样品常…