The laser-induced polymerization of powdered SiI4 has been investigated by time-of-flight (TOF) mass spectroscopy combined with density functional theory (DFT) calculations. In the positive ion spectra, three series of abundant clusters (SinI2n+1+ (n = 1-6), SinI4n/3+3+ (n = 7-15), SinI3n/2-7+ (n = 16-22)) were observed. DFT calculations have revealed that the abundant clusters are straight chains with iodine bridge in n = 1-6, multi-cyclic rings of pentagons in n = 7-15, and cages constructed by pentagons and hexagons in n = 1622. A silicon-rich six-membered ring, i.e., an unsaturated ring like benzene, was detected in less abundant clusters (C) 2007 Elsevier B.V. All rights reserved.