Carrying out a first-principles calculation assuming linear relationship between the electron density at Be nucleus and the electron-capture (EC) decay rate, we explained why B7 e@ C60 shows higher EC decay rate than B7 e crystal, which was originally found experimentally by Ohtsuki [Phys. Rev. Lett. 93, 112501 (2004)]. From the results of the calculation, we found that there are inequivalent four stable (i.e., lower energy) Be sites inside C60 and that center of C60 (C_ C60) is the most favorable site. For C_ C60, the electron density at the Be nucleus is the highest. It is also much higher than that at the Be nucleus in a Be crystal. Also, we estimated the expected electron density at the Be nucleus at room temperature by taking statistical average of the electron densities at the four Be nucleus sites using the Boltzmann distribution. The results of the calculation show fairly good agreement with the experimental results. In this paper, we focus on the detail of calculation, which was not fully demonstrated in the paper by Ohtsuki.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2008 Sep 23|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics