Occurrence of the solid-state photo-CIDNP effect at earths magnetic field

地磁场中固态光CIDNP效应的发生

• 批准号: 367704943
• 负责人: Professor Dr. Jörg Matysik
• 金额: --
• 依托单位: Institut für Analytische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/367704943?language=en
• 关键词: Occurrence; solid; state; photo; CIDNP

The solid-state photo-CIDNP effect, discovered in 1994 by Zysmilich and McDermott, has been shown to occur in several electron-transfer proteins such as photosynthetic reaction centers (RCs) and allows for enormous enhancement of NMR signals. Occurrence and strength of the effect strongly depend on the magnetic field strength. Up to now, the effect has been studied exclusively at the high fields available inside NMR magnets. Here we want to develop and apply a MAS-NMR shuttle system to allow for induction of the effect outside the magnet and NMR measurement in the center of the magnet. Hence, the proposed shuttle system will combine the advantage of low fields, i.e., high nuclear spin-polarization, with the advantage of high field, i.e. high chemical shift dispersion. Such system will allow for detailed studies on electronic structures, discovering more systems showing the effect and it will allow to explore the validity of the present theory.Theory also predicted the occurrence of the effect at weak magnetic fields including earths magnetic field conditions. With an advanced shuttle system, using a weak counter field, this theoretical prediction will be tested. In particular, we are interested in earths magnetic field effects on photosynthetic reaction center proteins and blue-light photoreceptors. Occurrence of the effect in reaction centers at earths field would suggest a functional relevance of nuclear spin-hyperpolarization of the efficient electron transfer. A successful experiment on blue-light photoreceptors would strengthen the proposal that light-dependent magnetoreception in animal navigation relies on magnetic-field dependent chemical reactivity. Hence, ideally our experiments will provide some experimental evidence on a bio-spintronic spin-valve in photosynthesis and on electron-electron-nuclear spin-dynamics controlling animal navigation.

固态光CIDNP效应，由Zysmilich和McDermott于1994年发现，已被证明发生在几种电子转移蛋白质中，如光合反应中心（RC），并允许极大地增强NMR信号。效应的发生和强度强烈地依赖于磁场强度。到目前为止，该效应仅在NMR磁体内部可用的高磁场下进行了研究。在这里，我们希望开发和应用MAS-NMR穿梭系统，以允许在磁体外部感应效应并在磁体中心进行NMR测量。因此，所提出的穿梭机系统将联合收割机结合低场的优点，即，高核自旋极化，具有高场的优点，即高化学位移色散。这样的系统将允许对电子结构进行详细的研究，发现更多显示该效应的系统，并将允许探索本理论的有效性。理论还预测了在弱磁场（包括地球磁场条件）下发生的效应。随着先进的穿梭机系统，使用弱反磁场，这一理论预测将得到验证。特别是，我们感兴趣的是地球磁场对光合反应中心蛋白质和蓝光光感受器的影响。在地球磁场的反应中心发生的效应表明有效电子转移的核自旋超极化的功能相关性。一项成功的蓝光光感受器实验将加强动物导航中依赖于光的磁感受依赖于磁场依赖的化学反应的建议。因此，理想情况下，我们的实验将提供一些实验证据的生物自旋电子自旋阀在光合作用和电子-电子-核自旋动力学控制动物导航。