The recently synthesized compound Gd2C2Cl2 contains distinct C2 dimers occupying the octahedral holes of two adjacent close-packed planes of Gd atoms. By assignment of an effective charge of -4 to C2, the observed C-C distance is rationalized from the C2MO diagram, since the n* level is half-occupied. In this contribution, we examine the electronic structure, while essentially no metal-metal bonding exists at all. The metallic behavior of Gd2C2Cl2 is due to the metal-carbon interaction leading to dispersion of the two C2 n* bands. We also consider the rotation of the C2 unit away from the tetragonal axis of the octahedral interstice as in the conceptual transition from CsC2 to FeS2 structure type.