Abstract 1,2-trans-diiodo-ethene (C2H2I2) – is an overlooked halogen bond donor, which demonstrate the distinct similarity of the geometry and directionality of I···I halogen bonds around the iodine atoms in its native and CpMn(CO)2(C2H2I2) π-complex crystals. Distortion of the planar geometry of C2H2I2 upon the π-coordination result the distortion of the native planar layered geometry of C2H2I2, so that [CpMn(CO)2](π-C2H2I2) features more complex I···I XB assisted 3D network. Unusual structural parallels between the native C2H2I2 crystals and solid iodine are discussed.

中文翻译：

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游离 1,2-二碘乙烯 (C2H2I2) 及其 π 络合物 [CpMn(CO)2](π-C2H2I2) 晶体中的卤素键

摘要 1,2-反式二碘乙烯 (C2H2I2) – 是一种被忽视的卤键供体，它证明了 I···I 卤键在其天然和 CpMn(CO) 中碘原子周围的几何形状和方向性的明显相似性。 )2(C2H2I2) π 复合晶体。C2H2I2 平面几何在 π 配位上的扭曲导致 C2H2I2 的原始平面分层几何扭曲，因此 [CpMn(CO)2](π-C2H2I2) 具有更复杂的 I···I XB 辅助 3D 网络. 讨论了天然 C2H2I2 晶体和固体碘之间不寻常的结构相似性。