1923年,几乎在发明质谱仪的同时,就在质谱图上观察到了弥散形的质谱峰,当时称之为阿斯顿(Aston)带。1946年,Hipple和Fox指出,这些弥散峰实际上是由亚稳跃迁离子所引起的。之后,有目的地观察质谱中的亚稳峰成为质谱学中的一个专门课题。六十年代,在有机质谱领域中提出了许多新的质谱方法,探索除电子轰击(EI)谱得到的电离源内的单电荷 In 1923, at the same time as the mass spectrometer was invented, a dispersive mass spectrum was observed on the mass spectrum, which was then called the Aston band. In 1946, Hipple and Fox pointed out that these diffuse peaks are actually caused by metastable ions. Afterwards, a purposeful observation of metastable peaks in the mass spectrum becomes a special topic in mass spectrometry. In the sixties, many new mass spectrometry methods were proposed in the field of organic mass spectrometry to explore the single charge in the ionization source obtained by electron bombardment (EI) spectroscopy