近年來，透過共價偶聯來擴展分子結構的方式引起了極大的關注。 在此種聚合物中，藉由可微調的電子特性，共軛π電子可以自由地移動。當與無機材料或是有機小分子相比，可調性在聚合物中更容易具體的實現，因此具有改進設備的巨大潛力。 通過表面生長的分子電路系統實現電子設備的小型化。 藉由表面合成原理所構建的共價鍵在過去十年中得到了極大的發展，表面輔助耦合可以合成無法在液體中合成的聚合物，不同的表面輔助偶聯反應已被使用為作用的主力。 眾所周知的 Wurtz 偶聯反應以金屬表面來作為示範，而不同於Ullmman 型偶聯反應中的芳基，烷基會參與Wurtz 反應的偶聯機制。 [5]在室溫下的非並苯骨架前體的合成可以形成碳-碳偶聯，具體來說，我們觀察到了一種依賴於溫度的耦合機制，分別由STM/STS 研究進行了密集的溫度/時間依據的相關實驗測試。 而PES、LEED、ARPES 等研究是由共同合作的實驗室一起完成的。

Covalently coupled extended molecular structure (Polymers) attracted huge attention in recent years. In such polymers, π electrons (conjugated) can move freely with the electronic properties finely tunable. This is more easily realized in polymers in comparison to inorganic materials or small organic molecules and has therefore huge potential for improved devices.

It offers the miniaturization of electronic devices through on-surface-grown molecular circuitry. The construction of covalent bonds through On-Surface Synthesis greatly developed during the past decade. Surface-assisted coupling can realize polymers, which are not possible in solution. Distinct surface-assisted coupling reactions have been used as the main workhorse. The well-known Wurtz coupling reaction is here demonstrated on a metal surface. Alkyl groups participate in the coupling mechanism of Wurtz reaction in difference to aryl groups in Ullmman type coupling reaction. The synthesis of [5]Phenacene backbone precursor results into a Carbon-Carbon coupling at room temperature. Specifically, a temperature-dependent and competing coupling mechanism was observed. An intensive temperature/time-dependent experiments with respective STM/STS study was done. The comparative studies by PES, LEED, ARPES was done in the collaboration.

Contents
Abstract i
摘要ii
Acknowledgements iii
Introduction 4
1 Instrumentation 6
1.1 UNISOKU USM1300 STM . . . . . . . . . . . . . . . . . . . . . . . 6
1.1.1 Load-Lock Chamber . . . . . . . . . . . . . . . . . . . . . . 7
1.1.2 Preparation Chamber . . . . . . . . . . . . . . . . . . . . . . 8
1.1.3 STM-Conversion Chamber . . . . . . . . . . . . . . . . . . . 10
1.2 Sample and Tip Holder . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.3 Working Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.3.1 Scanning Tunneling Microscope . . . . . . . . . . . . . . . . 13
1.3.2 Working Principle . . . . . . . . . . . . . . . . . . . . . . . . 14
1.3.3 Quantum Tunneling in a 1D . . . . . . . . . . . . . . . . . . 16
1.3.4 Bardeen Approach . . . . . . . . . . . . . . . . . . . . . . . 17
1.3.5 Scanning Tunneling Spectroscopy . . . . . . . . . . . . . . . 18
1.4 Sample Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1.4.1 Substrate Cleaning . . . . . . . . . . . . . . . . . . . . . . . 19
1.4.2 Molecule Depositon . . . . . . . . . . . . . . . . . . . . . . . 20
1.5 Calibration Studies of Sample Preparation . . . . . . . . . . . . . . 21
1.5.1 Sputtering Underheating . . . . . . . . . . . . . . . . . . . . 21
1.5.2 Molecular flux . . . . . . . . . . . . . . . . . . . . . . . . . . 23
1.5.3 Dirt Problem . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2 Research Background and Theory 27
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.1.1 1,2 BromoPhenyl-3,6 Phenyl-4,5-Pyrimidine benzene molecule
(BPPPB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.1.2 [n]Phenacene . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.2 Surface Assisted　Coupling . . . . . . . . . . . . . . . . . . . . . . 32
2.2.1 On-Surface Synthesis (OSS) . . . . . . . . . . . . . . . . . . 32
2.2.2 Wurtz Coupling . . . . . . . . . . . . . . . . . . . . . . . . . 33
2.2.3 3,10-Bis(Bromo-Methyl)-[5]Phenacene . . . . . . . . . . . . . 34
2.3 Halogens: A tale of friend and foe . . . . . . . . . . . . . . . . . . 35
2.3.1 Debrominization of Bromine . . . . . . . . . . . . . . . . . . 36
2.3.2 Debrominization by Atomic Hydrogen . . . . . . . . . . . . 36
3 Results and Discussions 38
3.1 1,2-BromoPhenyl-3,6-Phenyl-4,5-Pyrimidine Benzene molecule . . . 38
3.1.1 Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.1.2 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.1.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
3.2 [n]Phenacene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.2.1 Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.2.2 [10]Phenacene . . . . . . . . . . . . . . . . . . . . . . . . . . 48
3.2.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
3.3 3, 10-Bis(Bromo Methyl)-[5]Phenacene . . . . . . . . . . . . . . . . 56
3.3.1 Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
3.3.2 Self-Arrangement of Organometallic state at Room Temperature
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.3.3 Polymerization . . . . . . . . . . . . . . . . . . . . . . . . . 63
3.3.4 Polymers by Different Methods . . . . . . . . . . . . . . . . 67
3.3.5 High Temperature Annealing for bromine desorption . . . . 70
3.3.6 Debrominization by atomic Hydrogen Source . . . . . . . . . 74
3.3.7 Strange Surface formation . . . . . . . . . . . . . . . . . . . 82
3.4 Photoemission Spectroscopy (PES) and Low energy-electron Diffraction
(LEED) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
3.4.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
4 Summery 92
Appendix 99

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