The linear SiC7 cluster has been detected for the first time in Fourier transform infrared spectra observed when the products from the laser evaporation of Si/C rods were trapped in Ar at similar to 10 K. Comparison of C-13 isotopic shift measurements with the results of density functional theory (DFT) calculations confirms the identification of the nu(1)(sigma) mode of SiC7 at 2100.8 cm(-1).