The paper examines the effects of the porous high surface area silica support and the reaction temperature (175-550-degrees-C) on the dispersion and distribution of the titanium species formed during a single saturating reaction cycle of TiCl4, used in preparing Ti/silica samples by atomic layer epitaxy (ALE). Samples were analyzed by chemical etching, X-ray powder diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM), and X-ray photoelectron spectroscopy (XPS). The reactions were highly surface-controlled, i.e. controlled by the OH groups of silica, which determined the numbers of titanium atoms bound. Only amorphous titanium species was formed at lower reaction temperatures (< 300-degrees-C) and the amount decreased with increase in the reaction temperature. At temperatures above 300-degrees-C an increasing number of OH groups of silica most probably were directly chlorinated by TiCl4 leading to volatile Ti(OH)4-xClx (x = 1-3) species. This species then decomposed to TiO2. At 390-degrees-C and below, pure anatase was formed, whereas at 550-degrees-C the reaction led exclusively to rutile. The observed TiO2 Particles were platelike and evenly distributed throughout the silica particles. The largest particles are proposed to be formed in the largest silica pores with the highest density of OH groups and the smallest in the micropores. The silica pores were not blocked by TiO2 Particles, even though the diameter of most of the particles was about 500 nm. The XPS studies of the external silica surfaces revealed changes in Ti2p binding energy with increased reaction temperature. This was caused by size effects in XPS due to crystallization. In amorphous Ti/silica samples a decrease in binding energy with preheat temperature of silica was also observed. In addition, the XPS atomic Ti/Si ratios gave information on the distribution of titanium species within the silica particles and agreed with the observed platelike habit of the TiO2 particles.