Pseudo-two dimensional films/pseudo-one dimensional wire of metals and fullerene studied by positron annihilation spectroscopy.

通过正电子湮没光谱研究金属和富勒烯的伪二维薄膜/伪一维线。

• 批准号: 07650759
• 负责人: MURAKAMI Hideoki
• 金额: $ 1.34万
• 依托单位: Tokyo Gakugei University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650759/
• 关键词: Positron annihilation; Positronium; Porous materials; fullerene; 多孔性ガラス; 陽電子

The purposes of this study is to clarify the physical and chemical properties of thin films deposited on the micro-pore surfaces and those of thin wires packed in the micro pores of porous materials. Results are :1. The positronium yield and lifetime were measured on the potassium thin films deposited on the pore surfaces of a micro porous glass. The positronium intensity was decreased from 20% to 3%, and its lifetime was lengthened from 1.3ns to 6.0ns with the deposition of the film.2. The formation rate and lifetime of positroniums after packing of potassium metal into pores were close to those before the packing. We conclude that the positroniums are formed in the glass and they are not ejected into the pores.3. The measurements of positron lifetime and Doppler broadening were carried out on the nicro porous glass absorbing liquid benzene. The amount of benzene evaporation was obtained from the lifetime and line-shape parameter.4. Brominated fullerene was synthesized. The Doppler spectra for the brominated fullerene showed that the positron annihilate preferentially in the interstitial sites among the fullerene molecules.5. Alkali metals were doped into fullerene crystal. The change in positron lifetime made clear that some fraction of positrons annihilate in fullerene molecules while the others in interstitial sites among the molecules.

本研究的目的是阐明沉积在微孔表面的薄膜和填充在多孔材料微孔中的细丝的物理化学性质。研究结果如下：1.测量了沉积在微孔玻璃表面上的钾薄膜的正电子产额和寿命。随着薄膜的沉积，正电子强度从20%降低到3%，寿命从1.3 ns延长到6.0 ns。金属钾填充孔道后，正电子的形成速度和寿命与填充前接近。我们的结论是，正电子是在玻璃中形成的，它们没有被射入孔洞中。对吸收液体苯的NiCrO多孔玻璃进行了正电子寿命和多普勒展宽的测量。由寿命参数和线形参数得到了苯的蒸发量。合成了溴化富勒烯。溴化富勒烯的多普勒谱表明，正电子优先湮没在富勒烯分子间的间隙位置。将碱金属掺杂到富勒烯晶体中。正电子寿命的变化表明，一部分正电子在富勒烯分子中湮没，而另一部分正电子在分子间的间隙位置上湮没。