As well known, poly (vinyl alcohol) (PVA) forms the various kinds of iodine complexes (forms I, II and III) when the sample is immersed in the KI/I₂ aqueous solution of various iodine concentrations of 0.1–3 M. By immersing the PVA sample in more dilute solution of 0.001–0.05 M, a new X-ray diffraction pattern has been found (form IV). The quantitative analysis of the X-ray diffraction pattern combined with the resonance Raman data and the density functional theoretical calculation allowed us to derive the concrete structure model of form IV. The vertically-arrayed linear I₅⁻ ions are surrounded by the 6 PVA chains of planar-zigzag conformation to form the cylindrical structure. These cylinders are gathered together to form the hexagonal lattice. On the basis of the thus-determined structural information of a series of complexes, the transformation mechanism has been proposed for forms IV, I, II and III. Besides, the X-ray diffraction pattern of form IV was found to be similar to that measured for a commercial polarizer. The inner structure of the polarizer has been discussed concretely using the thus-revealed aggregation structure of form IV.

众所周知，当样品浸入 KI/I ₂水溶液中，碘浓度为 0.1-3 M时，聚乙烯醇 (PVA) 会形成各种碘配合物（I、II 和 III 型）。通过将 PVA 样品浸入 0.001-0.05 M 的更稀溶液中，发现了新的 X 射线衍射图（形式 IV）。X射线衍射图的定量分析结合共振拉曼数据和密度泛函理论计算使我们能够推导出IV型的混凝土结构模型。垂直排列的线性 I ₅ ^-离子被平面锯齿形构象的 6 个 PVA 链包围，形成圆柱形结构。这些圆柱体聚集在一起形成六边形点阵。根据由此确定的一系列配合物的结构信息，提出了 IV、I、II 和 III 型的转化机制。此外，发现形式 IV 的 X 射线衍射图类似于对商业偏振器测量的图。已经使用由此揭示的形式IV的聚集结构具体讨论了偏振器的内部结构。