本論文主要研究PF衍生物在不同溫度熱處理，形成奈米尺度的高分子單晶，根據結晶學解析結構，以電腦軟體模擬高分子堆疊結構情形，探討形成結構與其發光性質之間的關係。材料之選擇為具有相同主鏈以及接上相同碳數但不同種類側鏈。主要研究工具為穿透式電子顯微鏡、X光繞射儀、Cerius2電腦模擬。所得之結果可歸納以下幾點：
(1) PF8經由次微米尺寸單晶之培養與選區電子繞射，我們定出a相之結晶構造(斜方晶系，晶胞內有8根鏈，空間群P212121，晶格參數a = 2.56 nm, b = 2.34 nm, c = 3.32 nm,密度為1.041g/cm3)與分子疊積方式。相同地，另一衍生物PF26部份，我們定出a相之結晶構造(六方晶系，晶胞內有3根鏈，空間群P3，晶格參數a = 1.67 nm, b = 1.67 nm, c = 4.04 nm, 密度為0.991g/cm3)與分子疊積方式。
(2) 這一系列PF衍生物所得單晶結構，因不同種類的側鏈填入主鏈間空隙，形成主鏈具有不同扭轉角度的螺旋結構，並非全平面、全伸展的構形。因不同種類的烷基側鏈在空間中的排列，形成主鏈具有不同的扭轉程度，得到完全不同的結晶構造。由吸收及光致發光光譜得知，在結晶相的主鏈分子共軛長度變差，這結果造成放光波光為藍光。
(3) PF8之直鍊型側鍊會依序夾住相鄰主鍊，因此傾向於形成層狀排列；PF26之分支側鍊則僅填充主鍊間空間，造成六方堆積。

Structural evolution and its effect on optical absorption/emission behavior of derivatives of PFs upon heat treatment at different temperatures were studies by means of a combination of x-ray diffraction, transmission electron microscopy and molecular simulation.
The main physical characteristics from results of this study over a series of PFs with alkyl side-chains may be summarized as the following:
(1) The crystal structure of poly (9,9-di-n-octyl- 2,7-fluorene, PF8) and poly(9,9-bis(2- ethylhexyl)- 2,7-fluorene, PF26) are determined via a combination of selected area electron diffraction and molecular simulation. In PF8 case, there are 8 chains in an orthorhombic unit cell with dimensions a = 2.56 nm, b = 2.34 nm, c (chain axis) = 3.32 nm, space group P212121, and calculated density of 1.041 gcm-3. On the other hand, in PF26 case, there are 3 chains in a trigonal unit cell with dimensions a = 1.67 nm, b = 1.67 nm, c (chain axis) = 4.04 nm, space group P3, and calculated density of 0.991 gcm-3.
(2) All the simulation results indicate that branched side-chains in the case of PF26 tend to fill the space among backbones. In contrast, the linear side-chains in the case of PF8 appear to embrace the neighboring backbone, favoring formation of layered structure.
(3) As a consequence, co-planrity of PF backbones is decreased by the attached alkyl side-chains. This in turn results in lowered conjugation length, and in favor of blue light emission.

摘要 I
Abstract II
Table of Contents III
List of Figures VI
List of Tables X
Chapter 1.
Introduction 1
1.1. Conjugated polymers 1
1.2. Applications 3
1.3. Effects of inter-molecular interactions on the electronic structure of molecular systems 6
1.4. Objective of this work 8
1.5. Outline of this Dissertation 9
Chapter 2. Molecular Simulation via Energy Minimization 11
2.1. Introduction 11
2.2. Universal Force field 12
2.2.1. Parameters of the Force field 12
2.3. Basic Principle of energy minimization 13
2.4. Minimization algorithms 13
2.5. Box Dimensions (Unit Cell Dimensions) 16
2.6. Cutoff Radius 17
2.7. Nearest Image Conversion 19
2.8. System Equilibrium 19
2.9. Procedure of Molecular Simulation 21
2.10. Molecular simulation with Cerius2 engines 22
Chapter 3. Background on Crystallography System Operation 27
3.1. Molecular scale crystalline structure 27
3.2. Point Symmetry Elements and Operations 29
3.3. Two Dimensional Space Group and Point Group Symmetry 32
3.4. Symmetry Determination 34
3.4.1. Point group operation 34
3.5. Molecular Structure Steps in Crystal Structure Determination 39
3.5.1. Collect Intensity Data 39
3.5.2. Determination of Space Group 40
3.5.3. To solve the Crystal Structure 40
3.5.4. To complete and Refine the Structure 41
Chapter 4. Molecular Packing in Crystalline poly (9,9-di-n-octyl-2,7-fluorene) 44
4.1. Introduction 44
4.2. Experimental section 45
4.3. Space Group Determination 45
4.4. Molecular Modeling 48
4.4.1. Single-chain simulation 49
4.4.2. Trial-and-error method to fit experimental data 50
4.5. Molecular Packing 51
Concluding remarks 54
Chapter 5. Molecular Packing in Crystalline poly (9,9-bis-2-ethylhexyl-2,7-fluorene 71
5.1. Introduction 71
5.2. Experimental section 71
5.3. Space Group Determination 72
5.4. Molecular modeling 75
5.5. Molecular Packing 77
Concluding remarks 79
Chapter 6. Summary 94
References 96
Appendix 101

1.Kuhn, H. J. Chem. Phys. 1949. 17: p. 1198.
2.Pope, M.; Swenberg, C.E. Electronic processes in organic crystals. 1982. Clarendon press, Oxford.
3.Drefahl, G.; Kuhmstedt, R.; Oswald, H.; Horhold, H. H. Makromolekulare Chemie. 1970. 131: p. 89.
4.Shirakawa, H.; Louis, E. J.; MacDiarmid, Chiang., Heeger, A. J. J. Chem. Soc., Chem. Comm. 1977: p. 578.
5.Chiang, C. K.; Fincher, C. R.; Park, Y.W.; Heeger, A.J.; Shirakawa, H.; Louis, E. J.; Gau, S. C.; MacDiarmid, A. G. Phys. Rev. Lett. 1977. 39: p. 1098.
6.Baeriswyl, D.; Jeckelmann, E. The Hubbard model its physics and mathematical physics, 2nd ed. 1995. Plenum press, New York.
7.Peierls, R. E.; Quantum Theory of Solids. 1955. Clarendon press, Oxford.
8.Heeger, A. J.; Kivelson, s.; Schrieffer, J. R.; Su, W. P. Rev. Mod. Phys. 1988. 60, p. 781.
9.Heeger, A. J. Angew. Chem. Int. Ed. 2001. 40. p. 2591.
10.Bredas, J.L.; Cornil, J.; Heeger, A. J. Adv. Mater. 1996. 8: p. 447.
11.Miranda, P. B.; Moses, D.; Heeger, A. J. Phys. Rev. B. 2001. 64: p. 081201(R).
12.Alvarado, S. F.; Seidler, P. F.; Lidzey, D. G.; Bradley, D. D. C., Phys. Rev. Lett, 1998. 81: p. 1082.
13.Chandross, M.; Mazumdar, S.; Jeglinski, Wei. X.; Vardeny, Z.V.; Kwock. E.W.; Miller, T.M., Phys. Rev. B, 1994. 50: p. 14702.
14.Van der Horst, J. -W.; Bobbert, P. A.; Michels, M. A. J.; Bassler, H. J. Cehm. Phys. 2001. 114: p. 6950.
15.Gustafsson, G.; Cao, Y.; Treacy, G. M.; Klavetter, F.; Colaneri, N.; Heeger, A. J., Nature, 1992. 357: p. 477.
16.Greenham, N. C.; Moratti, S. C.; Bradley, D. D. C.; Friend, R. H.; Holmes, A. B. Nature. 1993. 365: p. 628.
17.Burroughes, J. H.; Bradley, D. D. C.; Brown, A. R.; Marks, R. N.; Mackay, K.; Friend, R. H.; Burn, P. L.; Holmes, A. B. Nature, 1990. 347: p. 539.
18.Braun, D.; Heeger, A. J. Appl. Phys. Lett., 1991. 58: p. 1982.
19.Yu, G.; Zhang, C.; Heeger, A.J., Appl. Phys. Lett., 1994. 64: p. 1540.
20.Yu, G.; Wang, J.; McElvain, J.; Heeger, A. J. Adv. Mater. 1998. 17: p. 1431.
21.Sariciftci, N. S.; Heeger, A. J. Int. J. Mod. Phys. B. 1994. 8: p. 237.
22.Koezuka, H. T.; Ando. T. Synth. Met. 1987. 18: p. 699.
23.Pei, Q. Y.; G.; Zhang, C.; Yang, Y.; Heeger, A. J. Science. 1996. 269: p. 1086.
24.Yu, G. P.; K.; Zhang, C.; Heeger, A. J. J. Electron. Matter. 1994. 23: p. 925.
25.Tessler, N.; Denton, G. J.; Friend, R. H., Nature, 1996. 382: p. 695.
26.Drury, C. J.; Mutsaers, C. M. J.; Hart, C. M.; Matters, D. M.; de Leeuw, D. M. Appl. Phys. Lett. 1998. 73: p. 108.
27.Friend, R. H.; Gymer, R. W.; Holmes, A. B.; Burroughes, J. H.; Marks, R. N.; Taliani, C.; Bradley, D. D. C.; Dos Santos D. A.; Bredas, J. L.; Logdlund, M.; Salaneck, W. R. Nature. 1999. 121: p. 397.
28.Brabec, C. J.; Sacriciftci, N. S.; Hummelen, J. C. Adv. Funct. Mater. 2001. 11: p. 15.
29.Wilson, J. S. ; Bhoot, A. S.; Seeley, A. J. A. B.; Kahn, M. S.; Kohler, A.; Friend, R. H. Nature. 2001. 413: p. 828.
30.Chen, S. H.; Su, A. C.; Chou, H. L.; Peng, G. Y.; Chen, S. A. Macromolecules. 2004. 37: p. 167.
31.Chen, S. H.; Su, C. H.; Su, A. C.; Chen, S.A. Manuscript submitted to J. Phys. Chem. B.
32.Roth, S., One-dimensional metals, 1995. VCH: Weinheim.
33.Kiess, H., Conjugated conducting polymers, Ed. 1992. Springer-Verlag: Berlin.
34.Redecker, M.; Bradley; D. D. C.; Inbasekaran, M.; Woo, E. P. Appl. Phys. Lett. 1999. 74: p. 1400.
35.Blatchford, J. W. G., T. L.; Epstein, T.L.; Bout vanden, Kerimo. J.; Higgins, D.A,; Barbara, P. F.; Fu, D. K.; Swager, T.M.; MacDiarmid, A. G. Phys. Rev. B. 1996. 54: p. 3683.
36.Nguyen, T. Q. D. V.; Schwartz, B.J., J. Chem. Phys., 1999. 110: p. 4068.
37.Hu, D.Y. J.; Wong, K.; Bagchi, B.; Rossky, P. J.; Barbara, P. F., Nature, 2000. 405: p. 1030.
38.Shi, Y. L. J.; Yang, Y. J. Appl. Phys. 2000. 87: p. 4254.
39.Lee, T. W.; P, O. O. Adv. Mater. 2000. 12: p. 801.
40.Liu, J. S. Y.; Ma, L.; Yang, Y. J. Appl. Phys. 2000. 88: p. 605.
41.Funahashi, M. H.; Je, I., Appl. Phys. Lett., 1997. 71: p. 602.
42.Tokuhisa, H. E.; M.; Tsutsui, T., Appl. Phys. Lett., 1998. 72: p. 2639.
43.Huang, Y. F., molecular packing and its effects on light-emitting properties of poly(1,4-phenylenevinylene)s, 2002. Ph. D. Thesis. Taiwan. R.O.C.
44.Rappe, A. K.; Casewit, C. J.; Colwell, K. S.; Goddard, III W. A.; Skiff, W. M. J. Am. Chem. Soc. 1992. 114: p. 10024.
45.Hahn, T., International Tables for Crystallograph. Brief teaching edition of volume A, Space-group symmetry, 1987. QD 908, I56.
46.Cullity, B.D., Elements of X-ray Duffraction, 2nd Ed. 1977. Addison-Wesley ISBN 0-201-01174-3.
47.Stout, G. H., x-ray structure determination, 1989. Wiley, New York.
48.Ladd, M. F. C. Palmer, R. A., Theory and Practice of Direct Method in Crystallography, 1980. New York, Plenum press.
49.Giacovazzo, C., Direct Methods in Crystallography, 1980. New York, Academic press.
50.Ladd, M. F. C., Palmer, R. A, Structure determination by X-ray Crystallography, 3rd Ed, 1993. Plenum press, QD 945 , L32.
51.Alexander, L. E., X-ray Diffraction Methods in Polymer Science, 1969. John Wiley & Sons Inc. QD 945 A43 c.2.
52.Schwartz, L. H.; Cohen J. B. Diffraction from Materials, 1987. Spring-Verlag Berlin, Heidelberg, QC 415, s38.
53.Glusker, J. P.; Kenneth N. Trueblood. Crystal structure analysis, A primer, 2nd Ed. 1985. Oxford University press, QD 945. G58.
54.Ladd, M. F. C., Symmetry in Molecules and Crystals, 1992. New York, Ellis Horwood.
55.Kraft, A. G.; A. C.; Holmes, A. B. Angew. Chem. Int. Ed, 1998. 37: p. 402.
56.Neher, D., Macromol Rapid Commun. 2001. 22: p. 1365.
57.Scherf, U.; List, E. J. W. Adv. Mater. 2002. 14: p. 477.
58.Chen, S. H.; Su, A. C.; Huang, Y. F.; Su, C. H.; Peng, G.Y.; Chen, S.A., Macromolecules, 2002. 35: p. 4229.
59.Chen, S. H.; Su, A. C.; Han, S. R.; Chen, S. A.; Lee, Y. Z, Macromolecules, 2004. 37: p. 181.
60.Grell, M.; Bradley, D. D. C.; Inbasekaran, M.; Woo, E.P. Adv Mater. 1997. 9: p. 798.
61.Teetsov, J.; Fox, M. A. J. Mater. Chem. 1999. 9: p. 2117.
62.Blondin, P.; Bouchard, J.; Beaupre, S.; Belletete, M.; Durocher, G.; Leclerc, M. Macromolecules. 2000. 33: p. 5874.
63.Kawana S.; Durrell,.M.; Lu, J.; Macdonald, J.E.; Grell, M.; Bradley, D. D. C.; Jukes, P. C.; Jones, R. A. L.; Bennett, S. L. Polymer, 2002. 43: p. 1907.
64.Chen, S. H.; Su, C. H.; Su, A. C.; Chen, S.A. Manuscript in preparation.
65.Grell, M.; Bradley, D. D. C.; Long, X.; Chamberlain, T.; Inbasekaran, M.; Woo, E. P.; Soliman, M. Acta Polym. 1998. 49: p. 439.
66.Grell, M.; Bradley, D. D. C.; Ungar, G.; Hill, J.; Whitehead, K. S. Macromolecules. 1999. 32: p. 5810.
67.Herz, L. M.; Philips, R. T. Phys. Rev. B. 2000. 61: p. 13691.
68.Cadby, A. J.; Lane, P. A.; Mellor, H.; Martin, S. J.; Grell, M.; Giebeler, C.; Bradley, D. D. C.; Wohlgenannt, M.; An, C.; Vardeny, Z. V. Phys. Rev. B. 2000. 62: p. 15604.
69.Winokur, M. J.; Slinker, J.; and Huber, D.L. Phys. Rev. B. 2003. 67: p. 184106.
70.Khan, A. L. T. B.; M. J.; Kohler. A. Syn. Met. 2003. 139: p. 905.
71.Lotz, B.; Lovinger, A. J.; Cais, R. E. Macromolecules. 1998. 21: p. 2375.
72.Bu, Z.; Yoon, Y.; Ho, R.M.; Zhou, W.; Jangchud, I.; Ebby, R. K.; Cheng, S. Z. D.; Hsieh, E. T.; Johnson, T. W.; Geerts, R. G.; Palackal, S. J.; Hawley, G. R.; Welch, M. B. Macromolecules. 1996. 29: p. 6575.
73.Ho, R. M.; Lin, C. P.; Hseih, P. Y.; Chung, T. M.; Tsai, H. Y. Macromolecules. 2001. 34: p. 6727.
74.Roe, R. J., Methods of X-ray and Neutron Scattering in Polymer Science. Oxford University press, 2000.
75.Vainshtein, B. K., Diffraction of X-rays by Chain Molecules. Elsevier publishing company, 1966.
76.Janietz, S.; Bradley, D. D. C.; Grell, M.; Giebeler, C.; Inbasekaran, M.; Woo, E. P, Appl. Phys. Lett, 1998. 73: p. 2453.
77.Zeng, G.; Yu, W. L.; Chua, S. J.; Huang, W, Macromolecules, 2002. 35: p. 6907.
78.Lieser, G.; Oda, M.; Miteva, T.; Meisel, A.; Nothofer, H. G.; Scherf, U.; Neher, D., Macromolecules, 2000. 33: p. 4490.