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在超高真空系统中制备了C6 0 的Yb填隙化合物薄膜 .用x射线光电子能谱研究了Yb和C6 0 结合过程中C 1s ,Yb4f和Yb 4d的变化 .利用Yb 4f和C 1s的谱峰强度确定出相纯样品的化学组分接近Yb2 .75C6 0 ,这一结果与晶体x射线衍射结果一致 .Yb 4f和Yb 4d的峰形与峰位表明化合物中Yb的价态为Yb2 + .相纯样品 (Yb2 .75C6 0 )的C 1s峰位相对于纯C6 0 向低结合能方向移动约 0 .5eV .C 1s结合能减小说明有Yb 6s电子转移到C6 0 的最低未充填分子轨道能带上 .结合能变化大小及峰宽的具体数值为进一步在薄膜样品上研究Yb2 .75C6 0 提供了表征样品的手段
In the ultrahigh vacuum system, a C6 0 thin film of Yb interstitial compound was prepared.The changes of C 1s, Yb 4f and Yb 4d during the binding of Yb to C 60 were studied by X-ray photoelectron spectroscopy.The spectrum of Yb 4f and C 1s The peak intensity determined that the chemical composition of the phase-pure sample is close to Yb2 .75C6 0, which is consistent with the results of X-ray crystallography. The peak shapes and peak positions of Yb 4f and Yb 4d indicate that the valence of Yb in the compound is Yb2 +. The C 1s peak of the phase-pure sample (Yb2 .75C6 0) shifts by about 0.5eV from the pure C6 0 toward the low binding energy. The reduction of the C 1s binding energy indicates that the lowest unfilled molecular orbital with Yb 6s electron transfer to C 60 The specific values of the binding energies and peak widths for further study of Yb2 on film samples provide a means to characterize the sample