Experiments that explore quantum principles while utilizing and reinforcing previous synthesis skills are excellent for engaging students and promoting the interconnected nature of chemistry. This experiment utilizes sophomore-level organic synthesis techniques to have students produce their own meso substituted porphyrins. The UV–vis absorption spectrum of the porphyrins is then collected and using the lowest π* ← π transition energy, the size of the conjugated circular π system and the length of a conjugated C–C bond can be calculated using the quantum particle-on-a-ring wave functions and energies. The model slightly overestimates the circumference of the ring and the C–C bond length. Students can then see and rationalize that there are clear molecular orbital considerations and substitution effects that cause these overestimations. With the ability to synthesize multiple substituted porphyrins and potentially insert metal cations, as well, this experiment offers a flexible and engaging way for physical chemistry students to synthesize their own molecules in the service of exploring quantum theory.

中文翻译：

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使用环上粒子预测合成卟啉的碳-碳键长度

探索量子原理同时利用和加强以前的综合技能的实验非常适合吸引学生并促进化学的相互关联性质。该实验利用大二水平的有机合成技术，让学生生产自己的内消旋取代卟啉。然后收集卟啉的紫外-可见吸收光谱，并使用最低的 π* ← π 跃迁能量，可以使用量子粒子计算计算共轭圆形 π 系统的尺寸和共轭 C-C 键的长度。 -环波函数和能量。该模型稍微高估了环的周长和 C-C 键长。然后，学生可以看到并合理化，存在明显的分子轨道考虑因素和替代效应导致这些高估。由于能够合成多种取代的卟啉并可能插入金属阳离子，该实验为物理化学学生提供了一种灵活且引人入胜的方式来合成自己的分子，以服务于探索量子理论。