Infrared spectra of Cr(CO)(6) adsorbed at different surface centers on gamma-alumina were investigated. The spectra of the probe complex revealed the existence of three types of strong Lewis centers and that of physisorbed Cr(CO)(6). In the case of the physisorbed complex O-h symmetry was widely conserved, and addition to strong Lewis centers led to lowering of the symmetry. The assumption of C-4 upsilon symmetry, caused by interaction of one CO group of the complex with a Lewis center, may explain the spectra. Approximate values for the integral extinction coefficients were determined.