在ge(100) - 2x1x1上化物反应中的竞争和选择性
Michael A Filler1, Collin Mui, Charles B Musgrave
1Departments of Chemical Engineering and Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|April 17, 2003
概括
研究了 (Ge) ((100) - 2x1表面上的基团结. 基组对直接结合不利,但基反应占主导地位,建议将其用作保护基.
科学领域:
- 表面科学是一门学科.
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 亚基功能组 (R-CN) 在有机合成中至关重要.
- 了解其在像这样的半导体材料上的表面化学成分对于开发新材料和新工艺至关重要.
研究的目的:
- 为了研究在Ge(100) - 2x1表面上的烯基功能组的结合行为.
- 确定影响该表面上各种含酸盐分子选择性和竞争的因素.
- 探索烯基组作为表面化学中的保护组的潜力.
主要方法:
- 使用多重内部反射红外光谱学的实验调查.
- 使用密度函数理论计算的理论分析.
- 探针分子的研究:乙二,二二,三二和四二.
主要成果:
- 由于热力学和动力学因素,在室温下,乙二在Ge(100) - 2x1表面上没有反应.
- 对于2-propenenitrile,主导的表面添加物是 [4+2] 循环添加产物 (ketenimine 拉伸在 1954 cm-1) 和 [2+2] C=C 循环添加产物 (烯拉伸在 2210 cm-1 附近).
- 3 - 丁烯和4 - 丁烯呈现接近1954厘米-1的振动模式,归因于对联烯的异构化.
结论:
- 仅涉及亚基功能组的直接结合途径在室温下对Ge{100) - 2x1在热力学上不利.
- 烯循环添加反应是多功能烯在这种表面上的主要途径.
- 化功能组可能在表面化学中作为真空兼容的保护组.
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