An e. s. r. study of AgCl-NaCl binary mixtures
An e. s. r. study of AgCl-NaCl binary mixtures
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一个 e。
DOI：
10.1098/rspa.1984.0030
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Eachus
中科院分区：
文献类型：
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作者：
M. T. Olm;M. Symons;R. Eachus
E. S. R.利用电子能谱研究了AgCl-NaCl固溶体的微观结构和电子性质。在γ-或u之后。V.辐照或低于77 K时，观察到Ag 2+作为空穴捕获中心，并且根据浓度，观察到局域或扩展的电子态。在银浓度低于10%时，局域电子态为Ag原子，在较高浓度时，局域电子态为传导电子，局限于AgCl团簇。在经典渗流极限（30mol%Ag）下，一个窄的导电电子c. e. S. R.在g = 1.888处观察到信号;这被归因于AgCl样带中的电子。产生这种信号的电子对晶体的扩展区域进行采样，并且其寿命大大延长，超过了纯AgCl中观察到的传导电子的寿命。梭e. S. R.线形作为电子浓度的函数进行了检查，并在低电子浓度下观察到的不对称性进行了讨论，在带尾的波函数本地化。异常长的传导电子寿命解释的传导电子无法移动到包含固定的Ag 2+中心的区域。我们认为，Ag 2+中心形成在AgCl样区域迅速与电子重组，而那些在更多的NaCl样区域是绝缘的。AgCl-NaCl固溶体为亚稳态，Ag ~（2+）和c. e. S. R.参数可用于跟踪初始相分离。
E. s. r. spectroscopy was used to study the microscopic structure and electronic properties of AgCl–NaCl solid solutions. After γ- or u. v. irradiation at or below 77 K, Ag2+ was observed as the hole-trapped centre, and depending on concentration, either localized or extended electron states were observed. At silver concentrations under 10%, the localized electron states were Ag atoms and at higher concentrations, they were conduction electrons confined to AgCl clusters. At the classical percolation limit (30 mol % Ag), a narrow conduction electron c. e. s. r. signal at g = 1.888 was observed; this was assigned to electrons in a AgCl-like band. The electrons giving rise to this signal sampled extended regions of the crystal and had a lifetime greatly extended over that observed for conduction electrons in pure AgCl. The c. e. s. r. lineshape was examined as a function of electron concentration and the observed asymmetry at low electron concentrations is discussed in terms of wavefunction localization in band tails. The exceptionally long conduction electron lifetime is explained in terms of the inability of the conduction electrons to move into zones containing the stationary Ag2+ centres. We suggest that Ag2+ centres formed in AgCl like regions rapidly recombine with electrons, while those in more NaCl-like regions are insulated therefrom. The AgCl-NaCl solid solutions were metastable, and the Ag2+ and c. e. s. r. parameters could be used to follow incipient phase separation.