A Muon Spectroscopic and Computational Study of the Microscopic Electronic Structure in Thermoelectric Hybrid Silicon Nanostructures
A Muon Spectroscopic and Computational Study of the Microscopic Electronic Structure in Thermoelectric Hybrid Silicon Nanostructures
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热电混合硅纳米结构中微观电子结构的μ子光谱和计算研究
DOI：
10.1021/acs.jpcc.9b11717
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Yue C
中科院分区：
文献类型：
--
作者：
Yue C
苯基乙炔包覆硅纳米颗粒（Phenyl-SiNPs）作为一种新型热电材料引起了人们的广泛关注。在此，我们报道了一种结合μSR和计算的方法来研究这种材料在溶液中的微观电子结构。为了比较，我们还研究了模型分子化合物四（2-苯乙基）硅烷。μSR测量结果表明，与模型化合物相比，Phenyl-SiNPs体系的μ介子各向同性超精细耦合常数μ（依赖于μ介子的自旋密度）大大降低。结果还表明，与模型化合物相比，苯基- sinps的a μ的温度依赖性是相反的符号，并且成比例地增大。Ab initioDFT方法使我们能够确定模型化合物中的μ子添加位点，而使用DFTB+和CASTEP进行的更广泛的计算研究为Phenyl-SiNPs系统中看到的耦合降低以及a μ对两种材料的不同温度依赖性提供了定性解释。计算表明，即使在存在有机帽的情况下，苯基- sinps在最高占据分子态的能级上的电子态密度也有所增加，这表明与四键模型化合物相比，该系统中电子传递增强的机制。
Phenylacetylene-capped silicon nanoparticles (Phenyl-SiNPs) have attracted interest as a novel thermoelectric material. Here, we report a combined muon spectroscopic (μSR) and computational study of this material in solution to investigate the microscopic electronic structure of this system. For comparison, the model molecular compound tetrakis(2-phenylethynyl)silane has also been investigated. μSR measurements have shown that the muon isotropic hyperfine coupling constant,Aμ, which depends on spin density at the muon, is greatly reduced for the Phenyl-SiNPs system when compared to the model compound. Results have also demonstrated that the temperature dependence ofAμfor the Phenyl-SiNPs is of opposite sign and proportionally larger when compared to the model compound.Ab initioDFT methods have allowed us to determine the muon addition site in the model compound, while a wider computational study using both DFTB+ and CASTEP offers a qualitative explanation for the reduced coupling seen in the Phenyl-SiNPs system and also the contrasting temperature dependence ofAμfor the two materials. Calculations suggest an increase in the density of electronic states at the energy level of the highest occupied molecular state for the Phenyl-SiNPs, even in the presence of an organic cap, suggesting a mechanism for enhanced electron transport in this system when compared to the tetrakis model compound.
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DOI：
10.2172/1218711
发表时间：
2006-11
期刊：
--
影响因子：
--
作者：
T. Hendricks;W. Choate
通讯作者：
T. Hendricks;W. Choate
具有导电配体的杂化硅纳米结构及其微观电导率
影响因子：
2.1
作者：
Tiezheng Bian;J. Peck;S. Cottrell;U. Jayasooriya;Y. Chao
通讯作者：
Y. Chao
μ子和μ化学：μSR数据的分析和解释
DOI：
10.1017/cbo9780511721717.007
发表时间：
1983
期刊：
The Review of scientific instruments
影响因子：
--
作者：
D. Walker
通讯作者：
D. Walker
影响因子：
41.2
作者：
Drew, A. J.;Hoppler, J.;Morenzoni, E.
通讯作者：
Morenzoni, E.
影响因子：
3.7
作者：
J. Sugiyama;H. Nozaki;I. Umegaki;K. Mukai;K. Miwa;S. Shiraki;T. Hitosugi;A. Suter;T. Prokscha
通讯作者：
J. Sugiyama;H. Nozaki;I. Umegaki;K. Mukai;K. Miwa;S. Shiraki;T. Hitosugi;A. Suter;T. Prokscha