【摘要】 防落素Ｂ系薄片状无色透明晶体，晶体的空间群为Ｃｃｌ５－Ｐ（ｚ１）／ｎ晶胞参数以ａ＝７．９５８（２）Ａ；ｂ＝３１．８５０（６）Ａ；ｃ＝５．２５０（３）Ａ；β＝１０６．５７（２）；Ｚ＝４；ρｏｏｓ＝１．２５克／厘米３，ρｏａｉｃ＝１．３４５克／厘米３，在四园衍射仪上用Ｍ０－Ｋα射线收录Ｉ＞１σ（Ｉ）独立衍射点１２９９个，晶体结构由直接法解出，经全矩阵最小二乘法精修，偏离因子＝０．１０２．结构分析表明，化合物中，苯环、支链羧基和正丁基三部分分别为三个平面；苯环与羧基平面交角为８、２°，苯环与正丁基平面交角为９．３°，羧基与正丁基平面交角为５．６°，苯环的－Ｃ－Ｃ－键平均键长为 １．３７０Ａ，化合物分子轴沿着晶胞ｂ轴方向排布。更多还原

【Abstract】 The compound PCPB （n-butyl-p-chlorphenoxyacetate） is a chip-like, co- lourless and trasparent crystal with the following crystallographic paprmeters: a=7. 938（2） A; b = 31. 859 （6） A;c=5.250（3） A;β=106. 57（2） °; Z = 4; ρobs=1.25g/cm3 ; ρcalc=1.345g/cm3. The space group is C₂h⁵-P（2₁）/n. The 1299 independent reflections with l>1σ（I） have been collected on a CAD-4 four-circle diffrac- tometer by means of Mo-Ka radiation. The structure is solved by direct me- thod and refined by least squares technique to a final discrepancy factor of R 0. 102. The results of our investigation reveal that the molecule consists of three planes by benzene ring, carboxyl branch link, and n-butyl respectively. The angle is 8. 2°, 9. 3°and 5.6°between the plane of benzene ring and carbo- xyl,benzene ring and n-butyl, and carboxyl and n-butyl respectively.The ave- rage bond length of benzene ring is 1.370A. The molecular axis of the com- pound is arranged along the direction of cell b axis.更多还原