KTiOPO4 single crystals doped with trivalent impurity ions of chromium were grown by spontaneous nucleation and seeded growth techniques. Structural refinement performed on the grown crystals by single crystal X-ray diffraction technique reveals that chromium ions occupy both the potassium sites with different filling coefficients. Incorporation of Cr3+ causes the absorption edge in the UV spectrum to shift towards the lower energy. The dependence of optical absorption coefficient with the incident photon energy in the UV-VIS region has been discussed. Optical and SEM studies indicate the existence of two-dimensional nucleation mechanisms. (C) 2003 Elsevier Science B.V. All rights reserved.