Electronic properties of CuS: Experimental determination of the magnetic hyperfine interactions and permanent electric dipole moment

The technique of intermodulated fluorescence has been utilized to record the sub-Doppler optical spectrum of gas-phase copper monosulfide, CuS. The magnetic hyperfine interactions in the A ²Σ^- (v = 0) and X ²Π_i (v = 0) states have been analyzed and the permanent electric dipole moment for the X ²Π_i state determined. The results have been compared with theoretical predictions and with those for CuO. The magnetic hyperfine parameters are significantly different from those of CuO whereas the dipole moment is nearly identical and these trends are consistent with the decrease in electronegativity of S compared to O.