This article reviews the recent development of the observation method of multiplet transient species bearing transition metals using microwave spectroscopy, which is one of the highest-resolution spectroscopic methods.Since it is difficult to efficiently produce such species in the gas phase and to analyze their complicated spectra with a high resolution spectroscopic method, they have been mainly studied through the observation of the electronic spectra with high sensitivity and low resolution. This new method with sputtering reaction enables to reveal the detailed physico-chemical character of such multiplet species.
Inductively coupled plasma mass spectrometry (ICP-MS) and ICP atomic emission spectrometry (ICP-AES) using argon ICP as an ionization or an excitation source have been widely utilized for trace elemental analysis . To overcome some limitations of conventional argon ICP new plasma sources have been investigated . In order to utilize other gas plasma for spectroscopic analysis, multi-gas ICP source was developed . And to reduce consumption of the sample solutions, droplet direct injection nebulizer (D-DIN) and microplasma source was designed and tested. In this article, recent works of these inventions are described.