利用高壓氣體由噴嘴(nozzle)噴入超高真空,由於絕熱膨脹使氣體分子的
溫度劇降而凝結成分子團簇(molecular clusters)。利用一部配有雷射多
光子游離(laser based multiphoton ionization)和電子碰撞游離(
electron impact ionization)裝置的飛行時間質譜儀(time-of-flight
mass spectrometer),來研究離子態分子團簇。由所得的飛行時間質譜來
分析各種離子態分子團簇所呈現的譜線強度,可得知離子態分子團簇的穩
定結構。本論文報導argon 、ammonia 、及carbon disulfide等的離子態
分子團簇的研究成果。

Neutral clusters,produced via supersonic expansion,are
subjected to multiphoton ionization by pulsed laser or electron
impact ionization by electron gun.The products of cluster ions
are investigated using a time-of-flight mass spectrometer.The
strong peaks on mass spectra are related to particularly stable
structures due to closely packings or special types of bondings.
Based on the analysis of their ion intensity distributions,
stable structures of cluster ions are deduced.In this paper,
cluster ion systems of argon、ammonia、 and carbon disulfide
are investigated and reported.
Neutral clusters,produced via supersonic expansion,are