Gadolinium systems offer a unique platform to investigate magnetically coupled ions, the analysis of said systems is of interest to the field of molecular magnetism. In Chapter 1 of this thesis, we introduce gadolinium species as a focus of study as well as some selected appearances in molecular magnetism literature. We also give a brief primer on magnetic parameterization and isotropy that are critical to our analysis. In Chapter 2 we describe the motivation for the synthesis of the phosphine scaffolded Gd(COT)I series and give a detailed overview of synthetic and characterization methods. Chapter 3 gives a magnetic analysis of the phosphine series which displays evidence of antiferromagnetic coupling, as well as a comparison to a few selected ferromagnetically coupled dinuclear gadolinium complexes.