论文标题
从有限温度下的分子量子电动力学到核磁共振
From Molecular Quantum Electrodynamics at Finite Temperatures to Nuclear Magnetic Resonance
论文作者
论文摘要
在有限温度下分子量子电动力学（MQED）的代数重新制定应用于核磁共振（NMR），以便为重建比当前方法重建更详细的分子结构。常规的NMR理论基于有效的自旋模型，该模型理想地将核作为晶格$ L $中的固定点颗粒，而分子振动，键旋和质子交换会导致核的定位。因此，如果有效的自旋模型用于研究，那么有关分子结构的大量信息仍然隐藏在实验NMR数据中。 在本文档中，显示了如何从$ \ mathbb {r}^{3n} $上的量子机械概率密度$ \midψ^β（x）\ mid^2 $ on $ \ mathbb {r}^{3n} $，用于从NMR数据中重建$ n $ nuclei的连续空间分布。为此，显示了如何在有限温度下直接从MQED计算NMR光谱而无需涉及有效描述。通过在$ W^*$ - 动力学系统上使用KMS状态的纯化表示，可以解决使用无限维辐射场进行数值计算的基本问题。此外，结果表明，提出的方法纠正了对有效自旋模型的错误预测。概述了提出的方法可以应用于可以使用常见量子化学方法计算电子基态的任何分子系统。因此，提出的方法可以取代自1950年以来NMR理论的基础的有效自旋模型。
The algebraic reformulation of molecular Quantum Electrodynamics (mQED) at finite temperatures is applied to Nuclear Magnetic Resonance (NMR) in order to provide a foundation for the reconstruction of much more detailed molecular structures, than possible with current methods. Conventional NMR theories are based on the effective spin model which idealizes nuclei as fixed point particles in a lattice $L$, while molecular vibrations, bond rotations and proton exchange cause a delocalization of nuclei. Hence, a lot information on molecular structures remain hidden in experimental NMR data, if the effective spin model is used for the investigation. In this document it is shown how the quantum mechanical probability density $\midΨ^β(X)\mid^2$ on $\mathbb{R}^{3n}$ for the continuous, spatial distribution of $n$ nuclei can be reconstructed from NMR data. To this end, it is shown how NMR spectra can be calculated directly from mQED at finite temperatures without involving the effective description. The fundamental problem of performing numerical calculations with the infinite-dimensional radiation field is solved by using a purified representation of a KMS state on a $W^*$-dynamical system. Furthermore, it is shown that the presented method corrects wrong predictions of the effective spin model. It is outlined that the presented method can be applied to any molecular system whose electronic ground state can be calculated using a common quantum chemical method. Therefore, the presented method may replace the effective spin model which forms the basis for NMR theory since 1950.
