Topicity
（重定向自Diastereotopic）
![Figure 1. Diastereotopic hydrogens in achiral compounds.](/Images/godic/202501/08/DIASTERE5344.png")
![Figure 2. Diastereotopic hydrogens in a chiral metal complex.](/Images/godic/202501/08/DIASTER25344.png")
In stereochemistry, topicity is the stereochemical relationship between substituents and the structure to which they are attached. Depending on the relationship, such groups can be heterotopic, homotopic, enantiotopic, or diastereotopic.