title: Selective self-ion/molecule reactions in both external and internal source ion trap mass spectrometers.
abstract: Novel results on the selective self-ion/molecule reactions (SSIMR) in both external and internal source ion trap mass spectrometers are demonstrated. Selective self-ion/molecule reaction product ions were produced between the oxygenated and nitrogenated crown ethers. For the oxygenated crown ethers, self-ion/molecule reactions lead to the formation of the protonated ions, adduct ions of fragments ([M + F](+)) and [M + H(3)O](+), while the nitrogenated crown ethers produce [M + H](+), [M + CH](+) and [M + C(2)H(3)](+) ions.
authors.affiliation: Department of Chemistry, Tamkang University, Tamsui, Taipei Hsien, 25137, Taiwan, R.O.C. gou@mail.tku.edu.tw
authors.forename: H F
authors.initials: HF
authors.lastname: Wu
authors.forename: M Y
authors.initials: MY
authors.lastname: Ho