縮小微芯片器件（如傳統半導體）的技術正在接近其極限，並且在原子尺度上的精確設計具有挑戰性。精確石墨烯奈米帶的製造提供了一種新方法可根據特定應用的需要調整電子特性。自下而上的方法涉及通過表面催化劑的有機合成，例如前體設計和預合成的聚合物鏈形成，提供了生產原子尺度下精確石墨烯奈米帶的有希望的方法。因此，創建合適的分子構建模塊並了解分子間自組裝和偶聯反應位點的特性是重要的問題。
\hspace*{4mm}在這裡，我們提出了一種新合成的分子，PAL025擁有一個鋅紫質核心，兩個蒽接在旁邊，兩端都含有溴。我們將其沉積在室溫Au（111）和表面退火分子的結果，以引起受空間位阻和解離能位影響的耦合反應。

The technology to down-scale microchip devices such as traditional semiconductor is approaching its limits and the precise design at the atomic scale challenging. Fabrication of precise graphene nanoribbon (GNR) provides a new way of tuning electronic properties to the need of specific applications. Bottom-up approach which involves organic synthesis through surface catalyst such as precursor design and pre-synthesized polymer chain formation provides a promising process of producing atomically precise GNR. Therefore, creating suitable molecular building blocks and understanding the properties of self-assembling and coupling reaction sites in-between molecules are important issues.
Here we present a newly synthesized molecule, PAL025 possessing a Zn-Porphyrin core with two arms of anthracene and terminated with bromine at both ends. We deposited it onto room temperature Au(111) and result of annealing molecule on surface to induce coupling reaction influenced by steric hindrance and dissociation energy barrier.

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