Development of a future potential primary direct method for quantifying paramagnetic substances

在分析化学和化学计量学中，库仑法、重力法和凝固点下降法等“物质量的主要直接测量方法”发挥着重要作用。这些主要的直接方法可以测量各种化学品的纯度。我们开发了一种利用居里-魏斯定律的定量磁性分析方法，为未来的主要直接方法定量抗磁性矩阵中不配对电子的原子提供了可能。为了实验验证该分析方法的原理，对氧化钆和氧化硅的混合粉末样品以及三种含自由基的高纯有机化合物进行了定量分析。结果表明，该方法成功地定量了钆离子或稳定的硝基自由基，但分析值的相对不确定度约为5%。

Such as coulometry, gravimetry and freezing point depression method, 'primary direct methods of measurement for the amount of substance' plays an important role in both analytical chemistry and chemical metrology. These primary direct methods can measure purities of various chemicals. We have developed a quantitative magnetic analytical method using Curie-Weiss law for future potential primary direct method to quantify atoms with unpaired electrons in diamagnetic matrix. For the experimental validation of principle of this analytical method, powder mixture samples of gadolinium oxide and silicon oxide and three high-purity organic compounds with free radicals were quantified. As the results, this magnetic analytical method successfully quantified the gadolinium ion or stable nitroxyl radicals, although the relative uncertainty of analytical values were approximately 5%.