【摘要】：材料的結(jié)構(gòu)與性質(zhì)是凝聚物理學(xué)、材料科學(xué)、化學(xué)等相關(guān)領(lǐng)域非常關(guān)注的基礎(chǔ)問題之一。深入研究物質(zhì)的微觀結(jié)構(gòu)不但有助于我們改善材料的性能而且能夠指導(dǎo)我們發(fā)展新材料。含能材料在現(xiàn)代國防和民用經(jīng)濟建設(shè)中占據(jù)重要地位。雖然人類利用含能材料已有數(shù)百年歷史,但對于其微觀結(jié)構(gòu)的穩(wěn)定性和能量釋放機理的研究還相對缺乏。特別是從微觀層次認識含能炸藥的起爆機理一直是現(xiàn)代爆轟物理、兵器科學(xué)、高壓凝聚態(tài)物理、材料科學(xué)等多學(xué)科領(lǐng)域共同關(guān)注的重要科學(xué)問題。含能炸藥在點火起爆過程中涉及高溫高壓環(huán)境,經(jīng)歷著復(fù)雜的物理、化學(xué)變化過程。但從根本上來說,材料的物理和化學(xué)性質(zhì)與其結(jié)構(gòu)息息相關(guān),而研究含能材料在各種加載條件下發(fā)生爆炸的微觀機理就是要揭示其分子在極端條件下如何發(fā)生結(jié)構(gòu)轉(zhuǎn)變或分解反應(yīng)的問題。另外,研究壓力作用下含能材料的分子結(jié)構(gòu)變化對于認識其在起爆過程中的早期反應(yīng)途徑非常有益。因此,開展高壓下含能材料的結(jié)構(gòu)及穩(wěn)定性研究對理解其分解和點火起爆等微觀機理方面具有重要的科學(xué)意義�；谏鲜鰡栴},本文采用金剛石壓砧(DAC)和輕氣炮加載技術(shù),結(jié)合原位拉曼光譜技術(shù)、沖擊熱輻射技術(shù)以及第一性原理計算方法對幾種典型含能材料在高壓條件下的結(jié)構(gòu)穩(wěn)定性進行了研究,具體內(nèi)容為:首先,研究了硝基苯(NB)在高壓下的結(jié)構(gòu)穩(wěn)定性。硝基苯作為一種結(jié)構(gòu)最為簡單的芳香硝基化合物,通常被作為研究硝基苯胺類炸藥的模型物質(zhì)。采用DAC技術(shù)和原位拉曼光譜技術(shù),在0-10 GPa壓力范圍內(nèi)考察了硝基苯晶體的高壓結(jié)構(gòu)與分子振動特性。實驗發(fā)現(xiàn),在5 GPa壓力附近硝基苯發(fā)生了一次結(jié)構(gòu)的突變。為了深入理解實驗觀測結(jié)果,采用基于密度泛函理論(DFT)的第一性原理計算方法對硝基苯在高壓下的結(jié)構(gòu)響應(yīng)行為進行理論模擬研究,計算發(fā)現(xiàn)分子鍵長、鍵角、二面角等物理參量均在7 GPa壓力下發(fā)生一個不連續(xù)的跳變,預(yù)示著硝基苯在高壓下發(fā)生了結(jié)構(gòu)轉(zhuǎn)變。對照實驗和計算結(jié)果,我們認為硝基苯分子結(jié)構(gòu)的變化是由于持續(xù)增加的壓力促使其分子結(jié)構(gòu)扭曲以抵抗增加的相互作用力,繼而導(dǎo)致分子結(jié)構(gòu)發(fā)生調(diào)整;高壓下硝基苯拉曼光譜中有限的振動模式發(fā)生變化正是由于該分子結(jié)構(gòu)的調(diào)整所致。其次,研究了典型的含能材料硝基甲烷(NM)在沖擊高壓條件下的結(jié)構(gòu)及其穩(wěn)定性。從微觀層面認識含能材料的沖擊起爆機理是現(xiàn)代爆轟物理、高壓凝聚態(tài)物理等多學(xué)科領(lǐng)域關(guān)注的重要問題之一。我們選取硝基甲烷這一結(jié)構(gòu)最為簡單的硝基化合物作為研究對象,基于輕氣炮加載平臺結(jié)合瞬態(tài)拉曼散射技術(shù)和沖擊熱輻射原位測量技術(shù),研究了液態(tài)炸藥硝基甲烷的拉曼特征峰隨沖擊壓力的變化規(guī)律和沖擊起爆延遲時間。實驗結(jié)果表明,在沖擊起爆前硝基甲烷仍然保持其光學(xué)透明特征。獲得了硝基甲烷在沖擊誘導(dǎo)期間生成新產(chǎn)物的拉曼光譜。首次發(fā)現(xiàn)在沖擊高壓下C-H鍵率先斷裂的實驗證據(jù);新的實驗結(jié)果為研究其他含能材料的點火反應(yīng)以及沖擊起爆機理提供了參考數(shù)據(jù)。再者,研究了含能晶體1,3-二氨基-2,4,6-三硝基苯(DATB)在高壓條件下的結(jié)構(gòu)變化及其穩(wěn)定性。DATB是硝基苯胺類炸藥中一種重要的含能材料,與著名的高鈍感炸藥TATB的分子結(jié)構(gòu)非常類似,但對其在不同壓力下結(jié)構(gòu)及性質(zhì)的相關(guān)研究十分有限。本文采用色散修正密度泛函理論(DFT-D)計算方法,在0-15 GPa壓力范圍內(nèi)對DATB晶體的結(jié)構(gòu)及其穩(wěn)定性進行了研究。結(jié)果表明,在常壓條件下模擬計算的晶體常數(shù)、分子幾何結(jié)構(gòu)以及分子間相互作用特征均與實驗結(jié)果吻合。其次,晶格常數(shù)、分子幾何結(jié)構(gòu)和彈性常數(shù)隨壓力的變化趨勢均在7.5 GPa壓力附近發(fā)生突變;根據(jù)晶體穩(wěn)定性的力學(xué)判據(jù),發(fā)現(xiàn)DATB晶體在7.3 GPa左右已不穩(wěn)定,表明在7.5 GPa壓力附近DATB晶體發(fā)生了結(jié)構(gòu)失穩(wěn)。最后,研究了新型含能化合物3,4-二氨基-1,2,4三唑-1-氨基四唑-5-酮(ATO·DATr)在不同壓力下的結(jié)構(gòu)穩(wěn)定性。ATO·DATr具有較高的密度、良好的爆壓和爆速,被認為是潛在的鈍感含能材料。這類富氮含能化合物由于具有較高的氮元素和生成熱,且產(chǎn)物主要是環(huán)境友好的氮氣等優(yōu)點而備受關(guān)注。本文采用DFT-D計算方法,在0-50 GPa壓力范圍內(nèi)研究了 ATO·DATr的晶體結(jié)構(gòu)、狀態(tài)方程以及電子性質(zhì);同時,運用Hirshfeld表面和二維指紋圖方法考察了其晶體內(nèi)分子間相互作用的變化。結(jié)果表明,在零壓下計算的晶格常數(shù)、分子幾何結(jié)構(gòu)以及分子間相互作用與實驗值相一致。晶體的可壓縮性呈現(xiàn)出各向異性并隨著壓力的增加而減小,ATO · DATr的體積模量也比其他常見含能材料的要高;同時隨著壓力的增加晶體中的短程相互作用增強,涉及長程相互作用的de值減小,揭示出高壓下ATO · DATr晶體可壓縮性的減小與分子間相互作用的增強有關(guān)。
[Abstract]:Structures and properties of materials are one of the fundamental issues of great concern in condensed physics, material science, chemistry and other related fields. In-depth study of the microstructure of materials can not only help us improve the properties of materials but also guide us to develop new materials. Energetic materials play an important role in modern national defense and civil economic construction. However, it has been hundreds of years since the energetic materials were used by human beings, but the research on the stability of microstructure and the mechanism of energy release is still relatively scarce. The process of ignition and detonation of energetic explosives involves high temperature and high pressure, and undergoes complicated physical and chemical changes. But fundamentally, the physical and chemical properties of materials are closely related to their structures. To study the micro-mechanism of explosion of energetic materials under various loading conditions is to reveal the molecular structure of energetic explosives. In addition, it is very useful to study the molecular structure changes of energetic materials under pressure for understanding the early reaction pathways in the initiation process. Therefore, the study on the structure and stability of energetic materials under high pressure is helpful to understand the micro-machine such as decomposition and ignition initiation. Based on the above problems, the structural stability of several typical energetic materials under high pressure is studied by means of diamond anvil (DAC) and light gas gun loading technique, in situ Raman spectroscopy, thermal shock radiation technique and first-principles calculation method. The structure stability of nitrobenzene (NB) at high pressure has been studied. Nitrobenzene, as the simplest aromatic nitro compound, is usually used as a model material for the study of nitroaniline explosives. The high pressure structure and molecular vibration of NB crystals have been investigated by using DAC and in situ Raman spectroscopy in the pressure range of 0-10 GPa. In order to understand the experimental results, the first-principles calculation method based on density functional theory (DFT) was used to simulate the structure response behavior of nitrobenzene at high pressure. The molecular bond length, bond angle and dihedral angle were found. A discontinuous jump of physical parameters at 7 GPa pressures indicates a structural transition of nitrobenzene at high pressures. Contrasting the experimental and computational results, we believe that the change of the molecular structure of nitrobenzene is attributed to the continuous increase of pressure which leads to the distortion of its molecular structure to resist the increasing interaction force, and then leads to the molecular structure. Secondly, the structure and stability of a typical energetic material, nitromethane (NM), under shock high pressure were studied. The shock initiation mechanism of energetic materials was recognized as modern detonation physics from the microscopic level. The Raman characteristic peaks of liquid explosive nitromethane have been studied based on the light gas gun loading platform combined with the transient Raman scattering technique and the shock thermal radiation in situ measurement technique. The experimental results show that the optical transparency of nitromethane is maintained before shock initiation. Raman spectra of new products of nitromethane during shock induction are obtained. Furthermore, the structural changes and stability of energetic crystals 1,3-diamino-2,4,6-trinitrobenzene (DATB) under high pressure were studied. DATB is an important energetic material in nitroaniline explosives, and the molecule of famous highly insensitive explosive TATB. The structure of DATB crystals is very similar, but the research on the structure and properties of DATB crystals under different pressures is very limited. In this paper, the structure and stability of DATB crystals are studied in the pressure range of 0-15 GPa by using the dispersion-corrected density functional theory (DFT-D). Secondly, the lattice constants, molecular geometric structures and elastic constants change abruptly near 7.5 GPa pressure. According to the mechanical criterion of crystal stability, it is found that DATB crystal is unstable around 7.3 GPa, indicating that DATB crystal is unstable near 7.5 GPa pressure. Finally, the structural stability of a new energetic compound 3,4-diamino-1,2,4-triazole-1-aminotetrazole-5-one (ATO.DATr) at different pressures was studied. ATO.DATr is considered as a potential insensitive energetic material because of its high density, good detonation pressure and detonation velocity. In this paper, the crystal structure, equation of state and electronic properties of ATO DATr have been studied by DFT-D method in the pressure range of 0-50 GPa. The results show that the lattice constants, molecular geometry and intermolecular interactions calculated at zero pressure are consistent with the experimental values. The compressibility of the crystals is anisotropic and decreases with the increase of pressure. The bulk modulus of ATO. DATr is also higher than that of other energetic materials. The short-range interaction in the crystal is enhanced, and the de value involved in the long-range interaction decreases. It is revealed that the decrease of compressibility of ATO.DATr crystal under high pressure is related to the enhancement of intermolecular interaction.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：TB34

【參考文獻】

相關(guān)期刊論文 前10條

1 王雙潔;管萍;胡小玲;田甜;;基于唑類離子的含能離子鹽的研究進展[J];材料工程;2015年11期

2 韓奇鋼;班慶初;;小型超高壓裝置的設(shè)計原理及研究進展[J];高壓物理學(xué)報;2015年05期

3 郭峰;張紅;胡海泉;程新路;;Effects of hydrogen bonds on solid state TATB,RDX,and DATB under high pressures[J];Chinese Physics B;2014年04期

4 葛妮娜;姬廣富;陳向榮;魏永凱;;沖擊波下固相HMX的初始反應(yīng)機理[J];爆炸與沖擊;2013年S1期

5 朱衛(wèi)華;黃輝;黃亨建;肖鶴鳴;;三類炸藥晶體沖擊引發(fā)分解機理的從頭算分子動力學(xué)研究[J];含能材料;2013年05期

6 趙北京;劉福生;王文鵬;張寧超;馮立鵬;張明建;薛學(xué)東;;二級炮加載條件下高分辨激光瞬態(tài)光譜技術(shù)及液態(tài)苯的沖擊穩(wěn)定性研究[J];光譜學(xué)與光譜分析;2013年10期

7 陳源福;劉福生;張寧超;趙北京;王軍國;張明建;薛學(xué)東;;瞬態(tài)激光拉曼光譜測量系統(tǒng)及其在苯?jīng)_擊壓縮實驗中的應(yīng)用[J];高壓物理學(xué)報;2013年04期

8 常景;周曉林;武曉龍;;高壓下固相硝基甲烷光學(xué)性質(zhì)的第一性原理計算(英文)[J];四川大學(xué)學(xué)報(自然科學(xué)版);2013年05期

9 張力;陳朗;;高壓下固相硝基甲烷分解的分子動力學(xué)計算[J];物理學(xué)報;2013年13期

10 李永宏;劉福生;程小理;馬海云;張明建;薛學(xué)東;;氣炮加載實驗中光學(xué)窗口透射率測量技術(shù)及其應(yīng)用[J];高壓物理學(xué)報;2010年06期

相關(guān)博士學(xué)位論文 前5條

1 吳瓊;含能富氮化合物的分子設(shè)計、高壓行為和熱分解機理[D];南京理工大學(xué);2015年

2 顏婷婷;典型的氫鍵有機晶體的高壓研究[D];吉林大學(xué);2015年

3 徐凱;硝基甲烷及其分解產(chǎn)物的從頭算分子動力學(xué)研究[D];四川大學(xué);2014年

4 彭小娟;沖擊加載下液態(tài)光學(xué)窗口水的熱物理性質(zhì)及疏松金屬鐵的沖擊溫度測量問題研究[D];西南交通大學(xué);2012年

5 劉紅;含能材料的高壓行為和光譜學(xué)特性的原子模擬[D];西南交通大學(xué);2006年

相關(guān)碩士學(xué)位論文 前3條

1 王亞平;沖擊壓縮下液態(tài)硝基甲烷的拉曼光譜研究[D];西南交通大學(xué);2015年

2 趙北京;沖擊條件下苯分子結(jié)構(gòu)變化及穩(wěn)定性研究[D];西南交通大學(xué);2013年

3 陳源福;動態(tài)加載下苯的拉曼光譜研究[D];西南交通大學(xué);2012年

，

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