Nucleation parameters such as radius of critical nucleus, critical free energy change and interfacial tension have been investigated for the aqueous solution growth of zinc thiourea chloride (ZTC) single crystals. The formation of ZTC compounds was confirmed by single crystal X-ray diffraction and the functional groups are confirmed by FTIR analysis. Solubility of ZTC has been determined for various temperatures. Metastable zonewidth and induction period values have been determined in order to optimize the growth parameters. The interfacial tension values estimated using the experimentally determined induction period are found to be comparable with theoretical values. Bulk crystals of ZTC have been grown from the optimized growth parameters. (C) 2003 Elsevier B.V. All rights reserved.