In recent years double core-hole states are intensively studied since their chemical shifts provide detailed information about initial-state and relaxation effects in a molecule. We derived the Si 1 s(-1), 2s(-1) and 2p(-1) binding energies as well as the Si 2s(-2), 2(p-1)2p(-1), and 2p(-2) double-core hole binding energies of different SiX4 systems in order to derive the chemical shifts. Based on these results we created Wagner plots, which give insight in the initial state and the relaxation effects in the different molecules.