The pure rotational spectrum of (CuO)-Cu-65 in its ground X (IIi)-I-2 state was recorded in the 198-384 GHz spectral region using a dc-sputtering absorption spectrometer. The determined Cu-65(I=3/2) hyperfine parameters are a=214.1(35), b(F)=-483.6(94), c=72.5(95), d=134.5(34), and eQq(0)=-16.9(54) MHz, where a three standard deviation error estimate is given in parentheses. A plausible molecular orbital description for the X (IIi)-I-2 state based upon the determined parameters is given. (C) 1997 American Institute of Physics.