侧基取代的有机共轭聚合物中极化子动力学性质的研究
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摘要
基于一维紧束缚SSH模型,采用非绝热动力学方法,我们研究了:
     1.掺杂聚合物的静态性质以及杂质离子对极化子动力学过程的影响。(1)在聚合物中均匀加入杂质离子的数目不同,则聚合物材料带隙的宽度不同;随着杂质势强度的增加,带隙变得越来越窄;(2)在聚合物中加入相同的杂质势(VP>0),发现杂质离子对电子极化子和空穴极化子的运动速度影响不同。在电场下极化子被加速,达到饱和速度后与杂质离子发生碰撞,电子极化子与杂质离子(VP>0)碰撞时受到库仑排斥作用,类似于势垒;而空穴极化子与杂质离子(VP>0)碰撞时受到库仑吸引作用,类似于势阱,由于杂质离子对正负极化子的作用不同,造成了它们平均速度的差异。(3)正负极化子的平均速度与杂质离子之间的距离有关。当杂质离子之间距离较近时,如,两杂质离子相距六倍晶格常数距离时,电子极化子的平均速度远快于空穴极化子。此外,正负极化子的平均速度还随着杂质势强度的增加而减少。
     2.含有侧基聚合物的静态性质以及侧基对极化子动力学过程的影响。(1)在聚合物链中引入具有排斥电子作用的侧基,侧基上的电子易跃迁至主链,相当于N型半导体材料。相反,如果用吸引电子基团作为聚合物的侧基,主链电子易跃迁至侧基,相当于P型半导体材料。侧基的加入使得聚合物带隙中形成局域能级,深能级随着主链与侧基之间跃迁积分的增加向带隙中间靠近,而随着其侧基基团在位能的增加分别向导带和价带靠近;(2)由于电子极化子和空穴极化子与侧基碰撞时受到的相互作用不同,导致了电子和空穴极化子运动速度不同。如,两侧基之间相距十六倍晶格常数时,极化子与侧基碰撞后,电子极化子的速度远快于空穴极化子。电子极化子的平均速度随着跃迁积分的增加而减少,相反,空穴极化子的平均速度随着跃迁积分的增加而增加;另外,侧基之间的距离对电子和空穴极化子平均速度的影响不同。随着侧基之间距离的增加,电子极化子的平均速度基本不变,而空穴极化子的平均速度在侧基之间的距离为14-22个晶格常数时,平均速度明显变小。电子和空穴极化子的平均速度还随着侧基基团在位能的变化而变化。
Based on the one-dimensional tight-binding Su-Schrieffer-Heeger (SSH) model and by using a nonadiabatic molecular dynamic method, we studied some static properties of polymer and the dynamical process of polaron in a polymer chain.
     1. we investigated some static properties of polymer and the dynamical process of polaron in polymer with impurity ions. (1)It is found that the polymer band gap is different in polymer with different number of impurity ions. It is also found that the band gap of conjugated polymer decreases with the increasing of the impurities potential strength. (2) In polymer with the same impurity ions (VP>0), we found that the velocities of the electron and the hole polaron are different. The polaron is accelerated by an external electric field to arrive a stationary velocity, then the polaron will collide with impurities. There is the coulomb repulsion between electron polaron and impurity ions (VP>0), which is similar to the potential barrier, while there is the coulomb attraction between the hole polaron and impurity ions (VP>0), which is similar to the potential well. Electron and hole polaron have different coulomb interaction with impurity ions, which causes the polaron speed of plus and minus difference. (3)The average velocity of polaron is affected by the distance between impurity ions. When impurity ions have a little distance, for example, the distance of impurity ions is six times lattice constant, the average velocity of the electron polaron is faster than the hole polaron. In addition, it is found that the average velocity of polaron decreases with the increasing of impurities potential strength.
     2. We investigated some static properties of polymer and the dynamical process of polaron in a polymer chain with side radicals. (1) In the polymer chain with the electronic group with exclusion as side radicals, it is found that the electron is easy to transfer to the main chain, namely, N-type semiconductor material. On the contrary, if the electronic group with attractive replace side radicals, it is found that theπ-electron of the main chain is easy to transfer to the side radicals, namely, P-type semiconductor material. Local degenerate energy levels in the band gap are formed by adding the side radicals. Local energy levels approach to the center of the band gap with the increasing of the hopping integral (t1) between theπ-electron of the main chain and the unpaired electrons at the side radicals. And local energy levels approach to the valence band and conduction band with the increasing of the potential energy of the side radicals. (2) It is found that the velocities of the electron and the hole polaron are different due to the influence of side radicals, it is because polaron and side radicals have different interaction, which causes the polaron speed of plus and minus difference. The polaron is accelerated by an external electric field and arrives a stationary velocity, then the polaron will collide with the side radicals, when the distance of side radicals is sixteen times lattice constant, the velocity of the electron polaron is far faster than the hole polaron. It is shown that the average velocity of the electron polaron decreases with the increasing of the hopping integral (t1), but the average velocity of the hole polaron increases with the increasing of the hopping integral (t1). And it is found that the average velocity of the polaron is affected by the distance of side radicals, the average velocity of the electron polaron almost be a constant with the increasing of the distance of the side radicals, while the average velocity of the hole polaron decreases suddenly as the distance of the side radicals arrives 14-22 lattice constant. In addition, it is also found that the average velocity of the polaron relates to potential energy of the side radicals .
引文
[1] Ito T, Shirakawa H, Ikeda S. Simultaneous polymerization and formation of polyacetylene film on the surface of concentrated soluble Ziegler-type catalyst solution[J]. J Polym Sci, Polym Chem Ed, 1974, 12(1): 11-20.
    [2] Papathanassiou A N, Sakellis I, et al. Universal frequency-dependent ac conductivity of Conducting polymer networks[J]. Appl Phys Lett, 2007, 91(12): 12911-1-12911-3.
    [3] Tamura H, Bittller E R, et al. Nonadiabatic quantum dynamics based on ahierarchical electron-phonon model: Exciton dissociation in semiconducting polymer[J]. J Chem Phys, 2007, 127(3): 034706-1-034706-18.
    [4] MacDiarmid A G, Heeger A J. Organic Metals and Semiconductors: The Chemistry of Polyacetylene (CH) x, and Its Derivatives[J]. Synthetic Metals 1, 1979, 101-103.
    [5] Yong cao, Gang Yu and Alan J Heeger. Efficient, fast response light-emitting electrochemical cells: Electroluminescent and solid electrolyte polymers with interpenetrating network morphology[J]. Appl Phys Lett, 1996, 68(23): 3218-3220.
    [6] Kaufman J H, K.aufer J W, Heeger A J, MuaDiarmid A G. Electrochemical voltage spectroscopy of trans-(CH)x[J]. Phys Rev B, 1982, 26(4):2327-2330.
    [7] Heeger A J, Pethig R. Charge Storage and Charge Transport in Conducting Polymers: Solitons, Polarons and Bipolarons[J]. Series A, Mathematical and Physical Sciences, 1985, 314: 1528-1530.
    [8] K?hler A, dos Santos D A, Beljonne D,et al. Charge separation in localized and delocalized electronic states in polymeric semiconductors[J]. Nature, 1998, 392: 903-906.
    [9] Coropceanu V, Malagoli M, Silva Filho D A da,et al. Hole-and Electeon -Via rational Coupings in Oligoacene Crystals: Intramolecular Contributions[J]. Phys Rev Lett, 2002, 89(27): 275503-1-275503-4.
    [10] Burroughes J H, Bradley D D C, Brown A R,et al. Light-emitting diodes based on conjugated polymers[J]. Nature, 1990, 347: 539-541.
    [11] Friend R H, Gymer R W, Holmes et A B,et al. Electroluminescence in conjugatedpolymers[J]. Nature, 1999, 397: 121-128.
    [12] Sirringhaus H, Kawase T, Friend R H, et al. High-Resolution Inkjet Printing of All-Polymer Transistor Circuits[J]. Science, 2000, 290: 2123 - 2126.
    [13] Natalie Stutzmann, Richard H Friend, Henning Sirringhaus. Self - Aligned, Vertical - Channel, Polymer Field - Effect Transistors[J]. Science, 2003, 299: 1881-1884.
    [14] Pejakovié D A, Kitamura C, Miller J S, et al. Photoinduced Magnetization in the Organic-Based Magnet Mn(TCNE)x y(CH2Cl2) [J]. Phys Rev Lett, 2002, 88(5): 057202-1-057202-4.
    [15] Plachy R, Pokhodnya K I, Taylor P C, et al. Ferrimagnetic resonance in films of vanadium [trtracyanoethanide]x, grown by chemical vapor deposition[J]. Phys Rev B, 2004, 70(6): 064411-1-064411-12.
    [16] 奥康纳. 化学基础[M]. 高等教育出版社, 1987. 30-34.
    [17] R. E. Peierls. Quantum Theory of Solid[M] (Oxford University Press, London),1955.8-9.
    [18] 孙鑫. 高聚物中的孤子和极化子[M]. 四川教育出版社,1987. 31-36.
    [19] Park M A D Y W, Heeger A J and MacDiarmid A G. Electrical transport in doped polyacetylene[J]. J Chem Phys, 1980, 73(2): 946-957.
    [20] Su J S W P, Heeger A J. Soliton in polyacetylene[J]. Phys Rev Lett, 1979, 42(25): 1698-1701.
    [21] Su J S W P, Heeger A J. Soliton excitations in polyacetylene[J]. Phys Rev B, 1980, 22(4): 2099-2111.
    [22] Su W P, Schrieffer J R. Soliton Dynamics in Polyacetylene[J]. Proc Natl Acda Sci USA, 1980, 77: 5626-5629.
    [23] Sun X, Fu R L, Yonemitsu K, et al. Photoinduced phenomenon in polymers[J]. Phys Rev A , 2001,64(3):032504-1-032504-7.
    [24] Campbell D K, Bishop A R. Solitons in polyacetylene and relativistic- field-theory models[J]. Phys Rev B, 1981, 24(8): 4859-4862.
    [25] Blumstein A, Samuelson L. Highly Conjugated Ionic Polyacetylenes: Thin-Film Processing and Potential Applications[J]. Advanced Materials, 1998, 10: 172-176.
    [26] Chang C K, Fincher C R, Park Y W, et al. Electrical Conductivity in DopedPolyacetylene[J]. Phys Rev Lett,1977, 39(17): 1098-1101.
    [27] Campbell I H, Smith D L. Excitation transfer processes in a phosphor-doped poly(p-phenylene vinylene) light-emitting diode[J]. Phys Rev B, 2002, 65(8): 085210-1-085210-8.
    [28] Kersting R, Lemmer U, Deussen M, et al. Ultrafast Field-Induced Dissociation of Excitons in Conjugated Polymers[J]. Phys Rev Lett, 1994, 73(10): 1440-1443.
    [29] Granstrom M, Inganas O. White light emission from a polymer blend light emitting diode[J]. Appl Phys Lett, 1996, 68(2): 147-1-147-3.
    [30] Yu G, Zhang C, Heeger A J. Dual-function semiconducting polymer devices: Light- emitting and photodetecting diodes[J]. Appl Phys Lett, 1994, 64(12):1540-1-1540-3.
    [31] Mori T, Obata K, Imaizumi K, et al. Preparation and properties of an organic light emitting diode with two emission colors dependent on the voltage polarity[J]. Appl Phys Lett,1996, 69(22):3309-1-3309-3.
    [32] Yu G, Pakbaz K, Heeger A J. Semiconducting polymer diodes: Large size, low cost photodetectors with excellent visible-ultraviolet sensitivity[J]. Appl Phys Lett,1994, 64(25):3422-1-3422-3.
    [33] Vissenberg M C J M, Jong M J M de. Theory of Exciton Migration and Field-Induced Dissociation in Conjugated Polymer[J]. Phys Rev Lett, 1996, 77(23): 4820-4823.
    [34] Tang C W, Van Slyke S A. Organic electroluminescent diodes[J]. Appl Phys Lett, 1987, 51(12): 913-915.
    [35] Jordan R H, Dodabalapur A, Strukelj M, et al. White organic electroluminescence devices[J]. Appl Phys Lett, 1996, 68(9): 1192-1194.
    [36] Wu W K, Kivelson S. Theory of conducting polymers with weak electron-electron interactions[J]. 1986, 33(12): 8546-8557.
    [37] Conwell E M. Hot electrons and impact ionization in poly(p-phenylene vinylene)[J]. Phys Rev B, 1998, 57(20): R12670-R12672.
    [38] Basko D M, Conwell E M. Stationary Polaron Motion in a Polymer Chain at High Electric Fields. Phys Rev Lett, 2002, 88(5):056401-1-056401-4.
    [39] Rakhmanova S V, ConwellE M. Polaron dissociation in conducting polymers by highelectric fields[J]. Appl Phys Lett, 1999, 75(11):1518-1520.
    [40] Johansson A, Stafstr?m S. Polaron Dynamics in a System of Coupled Conjugated Polymer Chains[J]. Phys Rev Lett, 2001, 86(16): 3602-3605.
    [41] Di b, Meng Y, An Z, et al. Dynamics of Polaron at Polymer/Polymer Interface[J]. Chin Phys Lett, 2008, 25(2): 679-682.
    [42] Yu J F, Wu C Q, Sun X, Nasu K. Breather in the motion of a polaron in an electric field[J]. Phys Rev B, 2004, 70(6): 064303-1064303-5.
    [43] An Z, Wu C Q, Sun X. Dynamics of Photogenerated Polarons in Conjugated Polymers[J]. Phys Rev Lett, 2004, 93(21): 216407-1-216407-4.
    [44] Liu X J, Gao K, Fu J Y, et al. Effect of the electric field mode on the dynamic process of a polaron[J]. Phys Rev B, 2006,74(17):172301-1-172301-4.
    [45] Basko D M, Conwell E M. Polaron Dynamics in a System of Coupled Conjugated Polymer Chains[J]. Phys Rev Lett, 2001, 86(16): 3602-3605.
    [46] Phillpot S R, et al. Interplay of disorder and electron-phonon coupling in models of polyacetylene[J]. Phys Rev B, 1987,35(14): 7533-7550.
    [47] Silva Geraldo Magela e, Yoshiyuki Ono. Dynamics of charge transfer in molecular switches Ⅱ.Effective potentials and Coulomb interaction[J]. Synth Met, 1998, 97: 195-203.
    [48] Pinheiro C da S, Silva G M e. Use of polarons and bipolarons in logical switches based on conjugated polymers[J]. Phys Rev B, 2002, 65(9): 094304-1-094304-5.
    [49] Yan Y H, An Z, Wu C Q. Dynamics of polaron in a polymer chain with impurities[J]. Eur Phys J B, 2004, 42: 157-163.
    [50] Heeger A J, Kivelson S, Schrieffer J R, et al. Solitons in conducting polymers[J]. Rev Mod Phys, 1988, 60(3): 781-850.
    [51] Blackman J A , Sabra M K. Interchain coupling and optical absorption in degenerate and nondegenerate polymers[J]. Phys Rev B, 1993, 47(23):15437-15448.
    [52] Hebner T R, Wu C C, Marcy D, et al. Ink-jet printing of doped polymers for organic light emitting devices[J]. Appl Phys Lett, 1998, 72(5):519-521.
    [53] Li Z J, An Z, et al. The pair of soliton_like distortions in organic ferromagneticconjugated polymers[J]. J Chem Phys, 1998, 109(22): 10082-10086.
    [54] Fang Z, Liu Z L,Yao K L. Theoretical model and numerical calculations for a quasi-one-dimensional organic ferromagnet [J]. Phys Rev B, 1994, 49(6):3916-3919.
    [55] Wang W Z, Liu Z L, Yao K L. Interchain coupling model for model quasi-one- dimensional π-conjugated organic ferromagnets[J]. Phys Rev B, 1997, 55(19): 12989- 12994.
    [56] Fang Z, Liu Z L, Yao K L. Spin configurations of π electrons in quasi-one-dimensional organic ferromagnets[J]. Phys Rev B, 1995, 51(2):1304-1307.
    [57] Xiong B,Wang W Z. Structural phase transition and soliton in an organic ferromagnetic polymer: Theoretical prediction[J]. Phys Rev B, 2005, 71(17): 174431-1-174431-6.
    [58] Wang W Z. Solitons in magnetic nanographite ribbons investigated with a Peierls-Hubbard model[J]. Phys Rev B, 2005, 71(9): 094407-1-094407-7.
    [59] Wang W Z, Yao K L, Lin H Q. Charge density wave transition and instability interchain coupled organic ferromagnets with next_ nearest_neighbor hopping interaction[J]. J Chem Phys, 1998, 108(7): 2867-2872.
    [60] Wang W Z. Model of a gate-controlled spin filter based on a polymer coupled to a quantum wire[J]. Phys Rev B, 2006, 73(23): 235325-1-235325-5.
    [61] Wang W Z. Ferromagnetism in a periodic Anderson-like organic polymer at half-filling and zero temperature[J]. Phys Rev B, 2006, 73(3): 035118-1-035118-7.
    [62] Wang W Z. Ground states in a quasi-one-dimensional triangular Hubbard model[J]. Phys Rev B, 2005, 72(12): 125116-1-125116-6.
    [63] Duan Y F, Yao K L. Ground states in a quasi-one-dimensional triangular Hubbard model[J]. Phys Rev B, 2001, 63(13): 134434-1-134434-4.
    [64] Takahashi M, et al. Discovery of a quasi-1D organic ferromagnet, p-NPNN[J]. Phys Rev Lett, 1991, 67(6): 746-748.
    [65] Macedo A M S, dos Santos M C, Coutinho-Filho M D, et al. Magnetism and Phase Separation in Polymeric Hubbard Chains[J]. Phys Rev Lett, 1995, 74(10): 1851-1854.
    [66] Nasu K. Periodic Kondo-Hubbard model for a quasi-one-dimensional organic ferromagnet m-polydiphenylcarbene: Cooperation between electron correlation andtopological structure[J]. Phys Rev B, 1986, 33(1): 330-338.
    [67] Jerome D, Mazaud A, Ribault M, et al. Superconductivity in a synthetic organic conductor (TMTSF) 2 PF 6[J]. J Phys Lett(paris), 1980, 41: L95-L97.
    [68] Parkin S, et al. Superconductivity in a New Family of Organic Conductors[J]. Phys Rev Lett, 1983, 50(4): 270-273.
    [69] Wu Wei kang. Nonlinear Optical Susceptibilities of a One-Dimensional Semiconductor [J]. Phys Rev Lett, 1988, 61(9): 1119-1122.
    [70] Heflin J R, Wong K Y. Zamani-Khamiri O and Gartio A F. Nonlinear optical properties of linear chains and electron-correlation effects[J]. Phys Rev B, 1988, 38(2):1573-1576.
    [71] Bernd. Richter, Stefun Kirstein. Excitation energy transfer between molecular thin layers of poly(phenylene vinylene) and dye labeled poly(allylamine) in layer-by-layer self-assembled films[J]. J Chem Phys, 1999, 111(11): 5191-5200.
    [72] Mizes H A, Conwell E M. Photoinduced charge transfer in poly(p-phenylene vinylene)[J]. Phys Rev B, 1994, 50(15):11243-11246.
    [73] Leger J M, Holt A L, Carter S A. Reversible thermochromic effects in poly(phenylene vinylene)-based polymers[J]. Appl Phys Lett, 2006, 88(11): 111901-1-111901-3.
    [74] Bloise A C, deAzevedo E R, et al. Solid-state nuclear magnetic resonance study of relaxation processes in MEH-PPV[J]. Phys Rev B, 2005, 71(17): 174202-174206.
    [75] Da filva M A T, Dias L F L, et al. Identification of the optically active vibrational modes in the photoluminescence of MEH-PPV films[J]. J Chem Phys, 2008, 128(9): 094902-1-094902-7.
    [76] Stafstrom S, Chao K A. Exact numerical investigation of the polaron-soliton generation in polyacetylene[J]. Phys Rev B, 1984, 29(12): 7010-7011.
    [77] Wang C L, Su Z B, Martino F. Bipolaron dynamics in nearly degenerate quasi-one -dimensional polymers[J]. Phys Rev B,1986, 33(2): 1512-1515.
    [78] Stafstr?m S, Chao K A. Polaron – bipolaron – soliton doping in polyacetylene[J]. Phys Rev B, 1984, 30(4): 2098-2103.
    [79] An Z, Li Z J, Liu Y, et al. Two-dimensional localized modes in conjugated polymers: the nonlinear electron-phonon coupling effect[J]. Chinese Phys, 2000, 9: 37-41.
    [80] Wu C Q, Qiu Y, An Z, Nasu K. Dynamical study on polaron formation in a metal/ polymer/metal structure[J]. Phys Rev B, 2003, 68(12): 125416-1-125416-5.
    [81] Brankin R W, Gladwell I, Shampine L F, RK-SUITE: Software for ODEIVPS (www.nelib.org).

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