Using the standard method of placing displacement vectors upon each ion in the basis (Ga and N), and reducing this displacement representation we obtain eight allowed vibrational modes in crystals with the space group C-6v(4). Decomposing the symmetrized Kronecker Product (KP) of the vector representation we obtain six first-order Raman active modes at the zone center of the Brillouin zone (BZ). We have determined the allowed combination and overtones of these first-order Raman modes (at k = 0). Performing inelastic light scattering experiments (ILS) we have verified the derived selection rules for combinations and overtones. (C) 2003 Elsevier Science B.V. All rights reserved.