Element Cr and Ligand Nitrogen

I have two sources and i want to b) Describe the purpose of the research and summarize the findings of each work.
c) Discuss the changes in bonding and chemical environment of your target element in each paper.
d) Compare and contrast the controlling chemical influences in the reactions or properties described in each of the papers.
e) Conclude with a discussion of the general observations and conclusions that can be drawn for these works. (I.e.: What ‘rules of thumb’ can be derived from your examination of these works?)