We report the orthoaxial and axial X-ray circular dichroism spectra of a homochiral single crystal of (Lambda-[Co(en)(3)]Cl-3}(2) center dot NaCl center dot 6H(2)O along with the linear dichroism of the same compound. The signs and magnitudes of the spectra confirm that the optical activity arises entirely from the interference between an electric quadrupole and electric dipole transition (EIE2 mechanism). By combining the results of the CD and LD spectra we have extracted the absolute values of the electric quadrupole and electric dipole contributions to the intensity of the 1s -> 3d transition and compare these to an ab initio calculation. (C) 2007 Elsevier B.V. All rights reserved.