Origin and use of quantum-rotor induced polarization in NMR

核磁共振波谱是一种用途广泛但不敏感的分析方法。为了提高灵敏度，动态核极化（DNP）等几种超极化方法受到了广泛的关注。量子转子诱导极化（quantum -rotor induced polarization， QRIP），又称haupt效应，起源于核自旋态与旋转量子态的耦合。在这里，在光谱学和理论的共同努力下，我们的目标是将QRIP效应发展成为一种更普遍适用的核磁共振波谱信号增强方法。由于这种效应主要基于无所不在的甲基，这可能在研究蛋白质和聚合物方面具有巨大的潜力。也有强有力的实验证据表明，环境对甲基的活性有影响，这超出了目前的理论。为此，我们将以三个里程碑为目标：(i)从显示该效应的测试样品中，我们将构建分子在其晶体环境中的结构模型；（ii）从对环境作用的理论理解中，我们希望提取能够诱导QRIP效应的结构基序；（iii）通过从结构数据库搜索中获得的预测来测试这些基序，以获得对QRIP效应的完整理论理解。

NMR spectroscopy is known as versatile but insensitive analytical method. To increase sensitivity, several hyperpolarisation methods as dynamic nuclear polarisation (DNP) receive presently great attention. Quantum-rotor induced polarisation (QRIP), also called Haupt-effect, originates from the coupling of nuclear spin states to rotational quantum states. Here, in a collaborative effort between spectroscopy and theory, we will aim for developing QRIP effects into a more generally applicable method for signal enhancement in NMR spectroscopy. Since the effect is mainly based on omnipresent methyl groups, this might have an enormous potential for studying proteins and polymers. There is also strong experimental evidence for involvement of the environment on the activity of a methyl group, which is beyond the present theory. To this end, we will aim for three milestones: (i) From test samples, showing the effect, we will construct structural models of the molecules in their crystal environment, (ii) from a theoretical understanding of the role of the environment we want to extract the structural motifs able to induce the QRIP effect, (iii) Testing these motifs by predictions obtained from structural databank searches to obtain full theoretical understanding of the QRIP effect.