感知或没有感知:可否通过感知分子探测异构效应?
Changwei Wang1, Fuming Ying, Wei Wu
1The State Key Laboratory of Physical Chemistry of Solid Surfaces, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
Journal of the American Chemical Society
|July 29, 2011
概括
在碳水化合物中的异构效应是有争议的. 计算证据表明,体传感器误解了甲基D-银酸中异构效应的形状变化,从而挑战了之前的说法.
科学领域:
- 碳水化合物化学 碳水化合物化学
- 计算化学的计算化学
- 频谱学是一种光谱学.
背景情况:
- 无分子效应在碳水化合物化学中至关重要,其起源在超和静电模型之间进行了辩论.
- 以前设计了一种体传感器,通过归因于电子密度转移的光谱变化来检测甲基D-银中的异构效应.
研究的目的:
- 通过计算来研究Cocinero等人观察到的光谱变化的起源. 与异构效应有关的.
- 为了确定体传感器是否准确地探测异构效应或形状差异.
主要方法:
- 密度函数理论 (DFT) 的计算被用来建模甲基D-银糖及其异常.
- 对原生分子和修改后的版本进行了能量和结构分析,其中包括氧与甲基的替代.
- 谱学属性被计算模拟以与实验数据进行比较.
主要成果:
- 计算证据表明,光谱变化源于α-和β-异构体之间的形状差异,而不是异构体效应.
- 用甲基取代内环氧,从而消除异构效应,产生了类似的光谱变化.
- 体传感器声称能够探测异构效应的能力,这些发现没有得到支持.
结论:
- 观察到的光谱变化主要是由于形状变化,而不是异质效应.
- 由Cocinero等人设计的类传感器. 不能准确地检测甲基D-银糖中的异构效应.
- 进一步调查异构效应的根本性质是有必要的.
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