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一、引言 化学诱导动态核极化(Chemically Induced Dynamic Nuclear Polarization,简称CIDNP)是一种在化学反应体系中观察到的NMR谱线强度反常的现象(常称之为极化谱,包括增强吸收和发射等)。1967年由Bargon和Fischer(西德)以及Ward和Lawler(美国)首先发现的。由于他们所研究的反应体系中涉及自由基,因此最初认为这种谱线强度反常现象是由于自由基中间体中的电子—核交叉弛豫引起的。这种机理通常称为:Overhauser型的动态核极化(Dynamic Nnclear Polarization简称DNP)。但很快就发现它不足以解释实验得到的结果,而CIDNP的命名却是这样因袭下来了。
I. INTRODUCTION Chemically Induced Dynamic Nuclear Polarization (CIDNP) is an abnormal phenomenon observed in the chemical reaction system of NMR spectral lines (often referred to as polarization spectrum, including enhanced absorption and Launch, etc.). First discovered in 1967 by Bargon and Fischer (West Germany) and Ward and Lawler (America). Because of the free radicals involved in the reaction systems they studied, the anomalies of the line intensity were originally thought to be due to electron-nuclear relaxation in free radical intermediates. This mechanism is commonly referred to as: Overhauser Dynamic Nolacle Polarization (DNP). But soon discovered that it was not enough to explain the experimental results, and CIDNP’s nomenclature did so.