本文選題：雙光子吸收　切入點：二聚效應　出處：《山東師范大學》2017年碩士論文　論文類型：學位論文

【摘要】：具有強雙光子吸收性質的有機分子材料,在諸多領域具有較大的應用潛能,例如3維光信息存儲,光動力療法和雙光子熒光顯微鏡(TPEM)等。尤其TPEM在活細胞組織中的應用,更是獲得了廣泛的關注。因此,探索有機雙光子吸收材料的潛能與應用,成為了科研工作者研究的熱潮。但是,在實驗材料、器材、費用等因素的限制下,在實驗上探尋材料性能的速度與效率并不盡如人意。近年來,通過量子化學計算理論研究雙光子吸收材料結構與性能的關系,成為了諸多科研者的工作重點。理論研究可以指導實驗分子的合成,從而大大節(jié)省了科研的時間與費用。目前,一系列具有π共軛中心、電子給體(D)和受體(A)的對稱或不對稱的電荷轉移分子(如D-π-D,D-π-A,D-A-D等)在理論和實驗上被廣泛研究。各種分子內結構因素(如分子平面性,給體和受體的強度,π共軛中心的電子特性等)和分子間相互作用(如聚集效應和溶劑效應)對雙光子吸收性質的影響有了充分地研究。因此,根據已有的分子結構與性質關系,理論設計性能優(yōu)良的雙光子吸收材料成為了可能。本文在雜化密度泛函水平上,理論研究了一系列由四苯基乙烯基團構建的有機分子體系,并討論了體系的結構與性質的關系。主要工作可分為以下二個部分:第一部分研究了一類四苯基乙烯衍生物雙光子吸收性質的二聚效應和同分異構效應;第二部分是基于四苯基乙烯衍生物,理論設計了一系列有機雙光子吸收分子結構,并計算了設計分子的雙光子吸收性質。一、四苯基乙烯衍生物雙光子吸收性質的二集效應和同分異構效應計算了一類新型四苯基乙烯衍生物ENPOMe分子及其同分異構體的雙光子吸收性質�？紤]了4種分子單體結構,統(tǒng)計了分子內各苯環(huán)平面間的二面角,計算了各單體結構的雙光子吸收截面。計算結果顯示,分子異構對雙光子吸收性質有重要影響,分子局部的平面性能夠增強分子的雙光子吸收強度。為了探索聚集效應,設計了12種共價鍵相連接的二聚體結構,并計算了它們的雙光子吸收性質。研究發(fā)現(xiàn),分枝的線性排列能夠有效增強材料的雙光子吸收性質。由于分枝與主干之間夾角相似的結構具有類似的分子內共軛通道和電荷轉移能力,所以分子的雙光子吸收性質也類似。此外,分子局部的平面性和整體的線性可能是實驗上觀測到的聚集誘導雙光子吸收增強的原因。二、基于四苯基乙烯衍生物雙光子吸收材料的分子設計在實驗分子的基礎上,綜合利用已有的雙光子吸收分子結構與性質之間的關系,理論設計了一系列有利于增強雙光子吸收截面的分子結構。通過改變分子中電子給體基團,增強給體的強度,設計了2種分子結構,相應的雙光子吸收強度均比實驗分子有所增強。同時,還發(fā)現(xiàn),當改變咔唑基與分子主體的連接方式時,可以顯著提高雙光子吸收強度。通過參考已有的實驗結果,設計了不同共軛橋連接的3種二聚體結構,結果顯示,采用乙烯和乙炔共軛橋連接的二聚體結構與實驗分子的二聚體結構相比,在長波范圍內,雙光子吸收有較大增強。因此,計算結果證實了我們的設計思路。理論設計的分子不僅具有較強的雙光子吸收,而且,由于分子均含有螺旋槳結構的四苯基乙烯基團,所以同時具有聚集誘導發(fā)光特性,可以成為優(yōu)良的雙光子熒光探針分子。
[Abstract]:With the organic molecular material with strong two-photon absorption properties, has great potential in many fields, such as 3 dimensional optical information storage, photodynamic therapy and two-photon fluorescence microscopy (TPEM). Especially TPEM in living tissues, it is widely concerned. Therefore, to explore the potential and application organic two photon absorption materials, has become a scientific research boom. However, in the experimental equipment, materials, costs and other factors limit, in the experiment to explore the speed and efficiency of material performance is not satisfactory. In recent years, the relationship through quantum chemical calculation theory of two-photon absorption material structure and performance, become many researchers focus on theoretical research. Synthetic molecules can guide the experiment, which saves the time and cost of scientific research. At present, a series of conjugated center electron donor (D) and Receptor (A) charge symmetric or asymmetric transfer molecules (such as D- -D D- -A PI, PI, D-A-D) in theory and experiment have been widely studied. The various factors in the molecular structure (such as molecular plane, donor and acceptor strength, conjugated center of electronic properties etc.) and intermolecular phase the interaction (such as aggregation effect and solvent effect) has been fully research on two-photon absorption properties. Therefore, according to the relationship between the molecular structure and properties, the theory of the design of excellent properties of two-photon absorption materials as possible. Based on the hybrid density functional theory research level, a series of four phenyl ethylene organic molecular systems group construction, and discusses the relationship between the structure and properties of the system. The main work can be divided into the following two parts: the first part is to study a class of four phenyl ethylene derivatives of two photon absorption properties of two poly effect and isomeric effect The second part is; four phenyl ethylene derivatives based on the theory, design a series of molecular structure of organic two-photon absorption, two-photon absorption properties and molecular design calculation. A two-photon, four phenyl ethylene derivatives of two-photon absorption properties of two in effect and the isomeric effect on a new class of four phenyl ethylene derivatives ENPOMe molecules and their isomers. Considering the absorption properties of 4 kinds of molecular monomer structure, the statistics of the dihedral angle between the benzene ring plane molecular two-photon, each monomer structure to calculate the absorption cross section is calculated. The results show that the molecular heterogeneity has an important effect on the two-photon absorption properties of planar molecules to local enhanced two photon absorption intensity. In order to explore the molecular aggregation effect, design two dimeric structure 12 covalently connected, their two-photon absorption properties were calculated. The results show that points Branch of the linear array can effectively enhance the two-photon absorption properties of materials. The structures are similar to the angle between the branch and the trunk has a similar intramolecular conjugated charge transfer and channel capacity, so the two-photon absorption properties of molecules are similar. In addition, the local molecular planarity and overall linear may be experimentally observed aggregation two photon induced absorption enhancement. Two, four phenyl ethylene derivatives of two photon absorption materials based on the molecular design of molecules based on the comprehensive utilization of the two-photon absorption molecular structure and properties of the theory, design a series is conducive to enhancing the two-photon absorption cross section by changing the molecular structure of electronic. The donor groups in the molecule, to enhance the strength, design 2 kinds of molecular structure, the corresponding two-photon absorption intensity than the experimental molecular improved. At the same time, also Found that when the connection mode change of carbazole and molecular entities, can significantly improve the two-photon absorption intensity. The experimental results with reference to the existing design, different conjugated bridge connecting 3 two dimer structure, results showed that the ethylene and acetylene conjugated bridge connecting two dimeric structure and experimental molecular poly two body structure than in the long wavelength range, two-photon absorption has greatly enhanced. Therefore, the calculated results proved that our design ideas. The molecular theory has not only design and better two-photon absorption, because, four phenyl vinyl group containing molecular structure of the propeller, so at the same time with aggregation induced emission, can become double photon fluorescent probe molecule excellent.

【學位授予單位】：山東師范大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：O625.12

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相關期刊論文 前1條

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本文編號：1637208