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本文中我们用Ｘ射线旋进照相观察了Ｂｉ２＋ｘＳｒ２－ｘＣｕＯｙ的晶体调制结构．实验结果表明ｘ＝０．２的单晶样品具有单斜对称性，其空间群为Ｂ２／ｂ（或Ｂｂ）．随着ｘ的增加，单斜畸变减小．我们测量了调制波矢随名义组成的变化规律，讨论了调制波矢在第一布里渊区的对称性质．对调制结构提出了几种可能的有公度模型．最后讨论了调制结构对超导电性的影响．
In this paper, we observed the crystal structure of Bi2 + xSr2-xCuOy by X-ray precession. The experimental results show that the single crystal samples with x = 0.2 have a monoclinic symmetry and the space group is B2 / b (or Bb). As x increases, monoclinic distortion decreases. We measured the variation of the modulated wave vector with the nominal composition, and discussed the symmetry of the modulated wave vector in the first Brillouin zone. Several possible models of public ownership are proposed for the modulation structure. Finally, the influence of the modulation structure on the superconductivity is discussed.