白金-ロジウム・フィラメント上の溶融けい酸塩から真空中で放出される正負イオンについて

抄録

Positive and negative ions from some molten silicates coated on a Pt-Rh (10%) filament have been measured using mainly a Hitachi RM-6E single-focusing mass spectrometer. The samples used are Li₂O-SiO₂ (mole ratio 2: 1 and 3: 1), Na2O-Si02 (1: 1 and 2: 1), K₂O-Si0₂ (1: 1), Cs₂0-Si0₂ (1: 1), PbO-Si0₂ (2: 1), Li₂0-Pb0-Si0₂ (2: 1: 1 and 1: 1: 2), and K₂O-PbO-Si0₂ (2: 1: 3). The temperatures of samples are read with an optical pyrometer, but the readings can not be corrected for emissivity and window transmission. The apparent temperaturerange is between 800°C and 1 400°C.
The negative ions O^-, O₂^-, SiO₃^-, MSi0₃^- (M=Li, K, and Cs), Rh0₂^-, RhO^-₃, and Pt0₂^- are found for all the systems investigated, except Pb0-Si0₂ (2: 1) and Li₂O-Pb0-Si0₂ (1: 1: 2). The proportions of these ions from K₂O-PbO-Si0₂ and K₂0-Si0₂ are particularly large compared with those from the other systems.
When PbO is added to a K₂0-Si0₂ system, the lowest temperature at which the negative ions are detected is lowered. The intensities of these ions are also increased by the addition of PbO.
The positive ions M⁺, M₂⁺, M₂0⁺ (M =Li, Na, K, and Cs), 0, ⁺ 0₂⁺, and Si⁺ are obtained from all systems, except PbO-SiO₂ (2: 1). The ions Li₃O⁺ and Li₃SiO₃⁺ are found in the mass spectra of Li₂0-Si0₂ and Li₂O-PbO-Si0₂. The ions containing Pb, such as LiPb0⁺, are found in the mass spectra of Li₂O-Pb0-Si0₂.