The dirhodium complex Rh 2(dfpma) 3Cl 4 (dfpma=bis(difluorophosphine)methyl-amine), in THF and in the presence of excess dfpma, undergoes photoreduction ( λ exc>304 nm) to Rh 2(dfpma) 3(η 1-dfpma) 2 via the two-electron mixed-valence compound, Rh 2(dfpma) 3Cl 2(η 1-dfpma). Conversion of Rh 2(dfpma) 3Cl 4 to Rh 2(dfpma) 3Cl 2(η 1-dfpma) is quantitative with a quantum efficiency of φ p 334=0.05(1); the subsequent conversion of Rh 2(dfpma) 3Cl 2(η 1-dfpma) to Rh 2(dfpma) 3(η 1-dfpma) 2 also proceeds quantitatively, though at a reduced quantum efficiency ( φ p 365=0.006(2)). The photochemistry of Rh 2 diphosphazanes has been expanded to include dirhodium cores coordinated by bis(bis(trifluoroethoxy)phosphine)methylamine, MeN[P(OEt F3) 2] 2 (OEt F3=OCH 2CF 3). The Rh 2{MeN[P(OEt F3) 2] 2} 3Cl 4, Rh 2{MeN[P(OEt F3) 2] 2} 3Cl 2L (where L=CO or CNBu t) and Rh 2{MeN[P(OEt F3) 2] 2} 3(CNBu t) 2 compounds have been prepared and the Rh 2(II,II) complex has been structurally characterized by X-ray diffraction analysis. Increased steric congestion of the bridging MeN[P(OEt F3) 2] 2 ligands about the dirhodium core distinguishes this Rh 2 diphosphazane series from its dfpma counterparts. The two-electron Rh 2(II,0)Cl 2 mixed-valence intermediate, which is crucial to sustaining four-electron photoreactivity in the Rh 2 dfpma series, is susceptible to ligand loss when three MeN[P(OEt F3) 2] 2 ligands span the bimetallic core, engendering a new photochemistry for this class of Rh 2 diphosphazane compounds.