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Y. Ito 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(1):171-174
The positron density distributions in C60 and K6C60 have been evaluated using the positron lifetime and Doppler-broadening spectroscopy for the annihilation radiation.In C60, positrons are distributed in the interstitial sites between the C60 molecules,which has been demonstrated by measurements of the temperature dependence of the Doppler-broadening of the annihilation radiation. On the other hand, the positron density distribution must be greatly changed in K6C60, because positrons are repelled by Coulomb interactions by the positively charged K atoms. It has been observed that there is an extremely short lifetime and a small Doppler-broadening component for the positron annihilation in K6C60. This component is considered to reflect the positron annihilation inside a C60 molecule. 相似文献