cation site symmetry

例句：

1. 1. The chemical reaction is governed bythe principles of chemical stoichiometry.
   化学反应遵循化学计量学原理。
2. 2. In stoichiometry, the ratio of reactants to products is crucial for understanding thereaction mechanism.
   在化学计量学中，反应物与产物的比率对于理解反应机制至关重要。
3. 3. The study of stoichiometry has led to significant advancementsin materials science and engineering.
   化学计量学的研究为材料科学和工程的进步做出了重要贡献。