Transitions associated with the vibrations v(1), v(1) + v(b)(1), v(1) + v(5)(1), and v(1) + v(5)(1) - v(5)(1) of the complex OC center dot center dot center dot Cl-2 have been rovibrationally analyzed for several isotopologues involving isotopic substitutions in Cl-2. Spectra were recorded using a recently constructed near-infrared (4.34 to 4.56 mu m), quantum-cascade laser spectrometer with cw supersonic slit jet expansion. Spectral analysis allowed precise determination of the v(5)(1) intermolecular vibration of OC-Cl-2(35) to be 25.977637-(80) cm(-1) These results were incorporated with other previously determined data into a spectroscopic database for generation of a five-dimensional morphed potential energy surface. This compound-model morphed potential with radial shifting (CMM-RS) was then used to make more accurate predictions of properties of the OC-Cl-2(33) complex including D-e = 544(5) cm(-1), D-0 = 397(5) cm(-1), v(3) = 56.43(4) cm(-1), and v(b)(1) = 85.43(4) cm(-1). The CMM-RS potential determined for OC-Cl-2 was also used to compare quantitatively many of the inherent properties of this non-covalent halogen bonded complex with those of the closely related hydrogen-bonded complex OC-HCl, which has a similar dissociation energy D-0. We found that in the ground state, the CO bending amplitude is larger in OC-Cl-2 than in OC-HCl.