Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
A. M. Introspection 3 11/13/XX Inorganic Metal complexes are so complicated, yet they are so interesting. So far in class we have looked at these complexes in a variety of ways, specifically from the view of acid/base and crystal field theory. They are extremely different and yet have an enormous overlap, the metals themselves. First and foremost, we applied the idea of acid base chemistry to metal complexes. The metals could act as Lewis Acids and could accept electron transfer from the surrounding ligands. Then, we had to determine which complexes were likely to form and the strength or stability of the said complex. So, we memorized that hard bases go with hard acids and soft bases go with soft bases. Although effective, the memorization became more of a looking up in a table. The information stopped there. We knew that like bonded with like, but we knew absolutely nothing about the arrangement of electrons or the preferred geometry. This is where crystal field theory enters. I have to say that I adore crystal field theory to a large extent. The information we have been able to abstract from it has been immense and the concepts have been interesting and relevant. For example, why is one metal complex blue and another complex with the same metal green? Just turn to crystal field theory. This theory is comprehensive and insightful. It can give you information regarding the position of the electrons, the splitting of energy levels in relation to the point group, and the magnetism. At first the theory was a big overwhelming. Honestly, it’s still overwhelming. However, by dissecting it piece by piece, rereading the notes and supplementing with the sections in the book, it began to come together for me. I began to understand why something was blue rather than green or why something was paramagnetic rather than diamagnetic. I know that there is still a great deal of learning to be done regarding metals and crystal field theory, but I am intrigued. This section was filled with a number of group activities. Although I am not normally a fan of group activities, these proved to be perfect for enhancing the understanding of the material and I was left wanting more, not less. The first activity had us uncover how the point group of a molecule might affect the splitting of orbitals and the arrangement of the electrons. My group was given a complex of Ni with two Cl ions and four connected nitrogen groups. It was complicated. It was daunting. Nonetheless, the results were interesting. We struggled together, as a group, with the ideas about which orbitals would be increasing in energy and which decreasing. We thoughtfully discussed how the one pointing directly toward the nitrogen groups would have to be higher than the one pointing toward the chloride groups. It all came down to field strength. By working through these ideas together, we were able to strategically decide the placement of the electrons. It was helpful to also see worked out examples of other point groups from other groups on the board. After working through a specific example on our own, it was much easier to properly understand why z2 was higher in energy for D3h, but x2-y2 was higher in energy for C4v and D4h. All in all, it was a successful activity. The same can be said for the color (ligand field strength) exercise. By working through each set of complexes and developing the patterns ourselves, I believe we will have a greater appreciation for the ordered list of complexes. Although crystal field theory can be difficult, I can honestly say that I prefer it to acid/base theories of metals.