高能化合物热解机理和撞击感度的理论研究-苯和苯胺类硝基衍生物

在DFT-B3LYP/6-31G*水平求得苯和苯胺类硝基衍生物的全优化分子几何和电子结构。通过非限制性 (U) B3LYP/6-31G*计算求得标题物各化学键离解能(BDE)。用UHF-PM3 MO方法求得引发键C-NO2键均裂反应的活化能(Ea)。以静态指标(键集居数、前线轨道能级差和硝基上净电荷)和动态理论指标(BDE和Ea) 阐明了热解引发机理,关联了实验撞击感度。运用SPSS程序关联静态和动态理论指标,表明它们可平行或等价地用作预示标题物的热解引发机理和撞击感度。     

反式-1,4,5,8-四硝基-1,4,5,8-四氮杂萘烷异构体热解机理与稳定性的理论研究

运用密度泛函理论和半经验分子轨道方法,对一系列高能杂环硝胺—反式-1,4,5,8-四硝基-1,4,5,8-四氮杂萘烷异构体的热解机理和稳定性进行了系统地计算研究。在B3LYP/6-31G**和PM3水平上,分别计算了标题物的化学键离解能(BDE)和热解反应活化能(Ea),并根据BDE和Ea数值考察了硝胺取代基对化合物稳定性和热解机理的影响;同时,还详细考察了BDE与Ea、化学键重叠布居数、前线轨道能级以及能隙之间的相关性。结果表明,由BDE、Ea和静态电子结构参数推断的标题物热稳定性和热解机理的结论基本是一致的,N-NO2键均裂是标题物的热解引发步骤,间位取代异构体较对位取代异构体稳定,而邻位取代的异构体稳定性最差。     

新型高能量密度化合物3,6-双(3,5-二硝基-1,2,4-三唑-1)-1,2,4,5-四嗪-1,4-二氧化物的性能预估及合成路线设计

采用C++自编译程序及组合原理,设计并筛选出一种未见报道的新型富氮类高能量密度化合物-3,6-双(3,5.二硝基.1,2,4-三唑.1)-1,2,4,5-四嗪-1,4-二氧化物,用B3LYP法,在6-31G**基组水平上得到该化合物全优化构型;在振动分析的基础上求得体系的振动频率、IR谱;通过键级分析得到热解引发键的键离解能(BDE);采用Monte-Carlo 方法预估了密度;设计等键等电子反应计算了生成焓;运用Kamlet-Jacobs公式预测爆速、爆压和爆热;运用Keshavarz 等推导的预估撞击感度H50的公式预测了撞击感度性能;并利用逆合成分析法设计其合成路线.结果表明:该化合物存在8个强吸收峰,校正后的热解引发键的BDE为264KJ·mol-1,稳定性较优;密度1.955 g·cm-3、生成焓901.72 kJ·mol-1、爆速9191.48 m·s-1、爆压39.32 GPa、爆热6705.15 j·g-1;撞击感度H50为55.85cm,低于黑索金(RDX)和奥克托今(HMx);以上性能均达到了高能量密度化合物的标准,且该化合物设计合成路线步骤较少、原料易得,有望得到广泛应用.     

哒嗪裂解反应机理的密度泛函理论研究

利用密度泛函理论(DFT)方法, 以哒嗪为煤的模型化合物, 在(U)B3LYP/6-31G(d,p)水平下计算了标题化合物的键布居数和键裂解能, 并对其热解机理进行了探讨. 在(U)B3LYP/6-311++G(d,p)水平下计算了热解过程中各物种的单点能, 并对总能量进行了校正. 结果表明, 标题物N-N键的布居数和裂解能均最小, 且各键裂解能随温度变化不大, 热解最终产物为HCN和乙炔, NH₃可能是HCN经过二次转换得到的. 采用过渡态理论计算了300~1900 K温度范围内热解的速率常数, 求得lnk与1/T的线性关系.     

双环-HMX结构和性质的理论研究

在DFT-B3LYP/6-311G*水平上, 计算研究了高能化合物四硝基四氮杂双环辛烷(双环-HMX) α和β两种异构体的结构和性质. 比较分子对称性、分子内氢键和环张力等几何参数以及分子总能量和前线轨道能级等电子结构参数, 发现α比β稳定. 分子中N—N键较长, N—N键集居数较小, 预示该键为热解和起爆的引发键. 基于简谐振动分析求得IR谱频率和强度. 运用统计热力学方法求得200～1000 K温度的热力学性质. 以非限制性半经验PM3方法探讨其热解机理, 求得各反应通道的过渡态和活化能, 发现热解始于侧链N—NO₂键的均裂. 还从理论上预测了该化合物的密度、爆速和爆压, 有助于寻求高能量密度材料(HEDM).     

1,3,5,7-四硝基金刚烷结构和性能的理论研究

在DFT-B3LYP/6-31G*水平下求得1,3,5,7-四硝基金刚烷的全优化分子几何和电子结构. 经简谐振动分析求得其IR谱并作归属. 由统计热力学求得其不同温度下的热力学性质. 以非限制性半经验MO方法探讨其热解机理, 求得各反应通道的过渡态和活化能, 发现热解始于侧链C—NO₂键的均裂. 还基于理论计算密度和生成热, 以Kamlet-Jacobs方程估算其爆速和爆压.     

苯的硝基和叠氮基衍生物的理论研究

在密度泛函理论B3LYP/6-31G*水平下优化了91个苯的硝基(NO₂)和叠氮基(N₃)衍生物的分子几何构型, 预测了它们的密度和生成热, 采用Kamlet-Jacobs方法计算了爆速和爆压, 筛选得到11种爆轰性能较好的高能量密度化合物(HEDC), 计算了它们的多个可能的热解引发键的键离解能(BDE)以及按“氧化呋咱机理”分解时的活化能(E_a). 结果表明, 当分子中有NO₂与N₃相邻时, 分解按“氧化呋咱机理”进行, 分解反应的E_a均大于100 kJ/mol|分子中没有NO₂和N₃相邻时, 热解始于C-NO₂或C-N₃均裂, 裂解的BDE都大于200 kJ/mol. 只含NO₂或N₃的7个物质的稳定性好于同时含NO₂和N₃的物质, 而只含N₃的物质的稳定性又好于只含NO₂的物质, 五叠氮苯和六叠氮苯具有很出色的爆轰性能和稳定性. 无论是能量还是稳定性方面, 筛选得到的11种物质基本符合HEDC的要求.     

环三甲撑三硝胺(RDX)结构和性质的DFT研究

环三甲撑三硝胺(RDX)是综合性能好、使用极广的高能炸药。本文用密度泛函理论(DFT)B3LYP方法,取6-31G*基组,求得其分子几何构型、电子结构、IR谱和热力学性质。全优化几何构型和电子结构均具有C3V对称性。在相邻原子之间以NNO2键的Mulliken集居数最小,表明其间电子分布较少,预示其为热解和起爆的引发键。IR谱与实验结果良好相符。计算所得298-1200K的热力学性质,对进一步深入研究RDX的反应和性质有助。     

Li(NTO)(H2O)2的热分解行为及其结构与性质的关系研究

摘要在水中合成了3-硝基-1,2,4．三唑-5-酮(NTO)的锂盐Li(NTO)(H2O)2,利用DSC,TG／DTG和IR方法研究了其金属配合物的热分解机理,并用Kissinger法、Ozawa法、积分法和微分法对标题配合物进行了非等温动力学研究,得到了热分解反应的动力学参数,确定了热分解第一阶段的动力学方程及配合物的热爆炸临界温度(Tb)为289．33℃．采取RHF／6-31G,DFT-RB3LYP／6-31G方法对标题化合物进行了几何全优化,并对其成键情况、电荷分布和化合物的稳定性进行了分析．     

环四甲撑四硝胺(HMX)结构和性质的DFT研究

用密度泛函理论(DFT)B3LYP方法,取6-31G基组,求得环四甲撑四硝胺分子的几何构型、电子结构、 IR谱和298～1200 K的热力学性质.全优化几何构型和电子结构均具有Ci对称性.在相邻原子之间以N-NO2键的Mulliken集居数最小,表明其间电子分布较少,预示其为热解和起爆的引发键.IR谱与实验结果良好相符.     

Synthesis and structure of hydroxyisoxazolidines and derivatives of hydroxylamine and alkenals

The reactions of N-substituted hydroxylamines with alkenals serve as a method for the synthesis of the corresponding 2-substituted 3(5)-hydroxyisoxazolidines. The reaction pathway is determined by the nature of the substituent attached to the nitrogen atom. Ring-chain isomerism has been detected in these newly obtained compoundsTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1270–1276, September, 1987.     

Synthesis and characterization of triazenide and triazene complexes of ruthenium and osmium

Triazenide [M(eta2-1,3-ArNNNAr)P4]BPh4 [M = Ru, Os; Ar = Ph, p-tolyl; P = P(OMe)3, P(OEt)3, PPh(OEt)2] complexes were prepared by allowing triflate [M(kappa2-OTf)P4]OTf species to react first with 1,3-ArN=NN(H)Ar triazene and then with an excess of triethylamine. Alternatively, ruthenium triazenide [Ru(eta2-1,3-ArNNNAr)P4]BPh4 derivatives were obtained by reacting hydride [RuH(eta2-H2)P4]+ and RuH(kappa1-OTf)P4 compounds with 1,3-diaryltriazene. The complexes were characterized by spectroscopy and X-ray crystallography of the [Ru(eta2-1,3-PhNNNPh){P(OEt)3}4]BPh4 derivative. Hydride triazene [OsH(eta1-1,3-ArN=NN(H)Ar)P4]BPh4 [P = P(OEt)3, PPh(OEt)2; Ar = Ph, p-tolyl] and [RuH{eta1-1,3-p-tolyl-N=NN(H)-p-tolyl}{PPh(OEt)2}4]BPh4 derivatives were prepared by allowing kappa1-triflate MH(kappa1-OTf)P4 to react with 1,3-diaryltriazene. The [Os(kappa1-OTf){eta1-1,3-PhN=NN(H)Ph}{P(OEt)3}4]BPh4 intermediate was also obtained. Variable-temperature NMR studies were carried out using 15N-labeled triazene complexes prepared from the 1,3-Ph15N=N15N(H)Ph ligand. Osmium dihydrogen [OsH(eta2-H2)P4]BPh4 complexes [P = P(OEt)3, PPh(OEt)2] react with 1,3-ArN=NN(H)Ar triazene to give the hydride-diazene [OsH(ArN=NH)P4]BPh4 derivatives. The X-ray crystal structure determination of the [OsH(PhN=NH){PPh(OEt)2}4]BPh4 complex is reported. A reaction path to explain the formation of the diazene complexes is also reported.     

Mass and NMR spectra of haplophyllidine and perforine and of their derivatives

Conclusions The mass and NMR spectra of haplophyllidine, perforine, and their derivatives have been studied. The influence of the open and cyclic forms of the molecular ion on the nature of the fragmentation has been discussed. The main routes of fragmentation of the compounds considered are due to the presence of substituents at C₈ and C₄.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 273–279, 1969     

Investigation of adhesion and mobility of polyurethane and epoxy-rubber glues and adhesives

The values of activation parameters in uncured and cured epoxy resins, rubbers, and blends thereof are investigated. The dependences of activation energy and adhesion strength of epoxy-rubber compositions on rubber content are determined. The correlation of adhesion and activation energy values for polyurethane rubber and epoxy-rubber compositions is shown.     

Crystal and molecular structure of aroyl- and acetylhydrazones of acet- and benzaldehydes

Aroyl- and acetylhydrazones of acet- (I) and benzaldehydes (IV) and benzoylhydrazones of acet- (II) and benzaldehydes (III) were studied by x-ray structural and quantum-chemical methods in order to establish their structures. Compund (I) was the EEZ structure in the crystal. Calculations and spectral data showed that the EEE form occurs in nonpolar solvents and in the gas phase. According to crystallographic data molecules (I)–(IV) are the E-isomers (relative to the N-N bond) and the hydrazone fragments are planar. Intermolecular N-H...O H-bonds from in the crystals. The data obtained suggest that the majority of acylhydrazones are conformationally rigid on dissolution although exceptions do occur. Apparently the reasons for the difference of acetyl- and benzoylhydrazones in electrocarboxylation reactions are electronic and not steric factors.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 75–81, January, 1991.     

Preparation and characterization of diarylphosphazene and diarylphosphinohydrazide complexes of titanium, tungsten and ruthenium and phosphorylketimido complexes of rhenium

Reaction of the proligand Ph2PN(SiMe3)2 (L1) with WCl6 gives the oligomeric phosphazene complex [WCl4(NPPh2)]n, 1 and subsequent reaction with PMe2Ph or NBu4Cl gives [WCl4(NPPh2)(PMe2Ph)] (2) or [WCl5(NPPh2)][NBu4] (3), respectively. DF calculations on [WCl5(NPPh2)][NBu4] show a W=N double bond (1.756 A) and a P-N bond distance of 1.701 A, which combined with the geometry about the P atom suggests, there is no P-N multiple bonding. Reaction of L1 with [ReOX3(PPh3)2] in MeCN (X = Cl or Br) gives [ReX2(NC(CH3)P(O)Ph2)(MeCN)(PPh3)](X = Cl, 4, X = Br, 5) which contains the new phosphorylketimido ligand. It is bound to the rhenium centre with a virtually linear Re-N-C arrangement (Re-N-C angle = 176.6 degrees, when X = Cl) and there is multiple bonding between Re and N (Re-N = 1.809(7) A when X = Cl). The proligand Ph2PNHNMe2(L2H) reacts with [(C5H5)TiCl3] to give [(C5H5)TiCl2(Me2NNPPh2)] (6). An X-ray crystal structure of the complex shows the ligand (L2) is bound by both nitrogen atoms. Reaction of the proligands Ph2PNHNR2[R2 = Me2 (L2H), -(CH2CH2)2NCH3 (L3H), (CH2CH2)2CH2 (L4H)] with [{RuCl(mu-Cl)(eta6-p-MeC6H4iPr)}2] gave [RuCl2(eta6-p-MeC6H4iPr)L] {L = L2H (7), L3H (8), L4H (9)}. The X-ray crystal structures of 7-9 confirmed that the phosphinohydrazine ligand is neutral and bound via the phosphorus only. Reaction of complexes 7-9 with AgBF4 resulted in chloride ion abstraction and the formation of the cationic species [RuCl(6-p-MeC6H4iPr)(L)]+ BF4- {(L = L2H (10), L3H (11), L4H (12)}. Finally, reaction of complex 6 with [{RuCl(mu-Cl)(eta6-p-MeC6H4iPr)}2] gave the binuclear species [(eta6-p-MeC6H4iPr)Cl2Ru(mu2,eta3-Ph2PNNMe2)TiCl2(C5H5)], 13.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

Kinetics and mechanisms of chlorine dioxide and chlorite oxidations of cysteine and glutathione

Chlorine dioxide oxidation of cysteine (CSH) is investigated under pseudo-first-order conditions (with excess CSH) in buffered aqueous solutions, p[H+] 2.7-9.5 at 25.0 degrees C. The rates of chlorine dioxide decay are first order in both ClO2 and CSH concentrations and increase rapidly as the pH increases. The proposed mechanism is an electron transfer from CS- to ClO2 (1.03 x 10(8) M(-1) s(-1)) with a subsequent rapid reaction of the CS* radical and a second ClO2 to form a cysteinyl-ClO2 adduct (CSOClO). This highly reactive adduct decays via two pathways. In acidic solutions, it hydrolyzes to give CSO(2)H (sulfinic acid) and HOCl, which in turn rapidly react to form CSO3H (cysteic acid) and Cl-. As the pH increases, the (CSOClO) adduct reacts with CS- by a second pathway to form cystine (CSSC) and chlorite ion (ClO2-). The reaction stoichiometry changes from 6 ClO2:5 CSH at low pH to 2 ClO2:10 CSH at high pH. The ClO2 oxidation of glutathione anion (GS-) is also rapid with a second-order rate constant of 1.40 x 10(8) M(-1) s(-1). The reaction of ClO2 with CSSC is 7 orders of magnitude slower than the corresponding reaction with cysteinyl anion (CS-) at pH 6.7. Chlorite ion reacts with CSH; however, at p[H+] 6.7, the observed rate of this reaction is slower than the ClO2/CSH reaction by 6 orders of magnitude. Chlorite ion oxidizes CSH while being reduced to HOCl, which in turn reacts rapidly with CSH to form Cl-. The reaction products are CSSC and CSO3H with a pH-dependent distribution similar to the ClO2/CSH system.