Star formation in the Galactic Center (GC) happens under unusual conditions, which include high gas temperatures, high velocity dispersions, and strong tidal shear (Spergel & Blitz 1992; Blitz et al. 1993). All these conditions may lead to an initial mass function (IMF) dominated by massive stars (Morris & Serabyn 1996). A history of chemical evolution dominated by massive stars is expected to result in enhancements of α-elements (Mg, Si, Ca, Ti) relative to Fe (Wheeler et al. 1989). This argument is the main motivation to study the abundance of Fe and Mg in GC stars.