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Recent progress in chemistry and material science caused new findings in nonclassical crystallization, known for more than 100-years1 . Self-organization in nonclassical crystallization is one of the few methods of synthesis of highly-oriented structures called mesocrystals (MC).2 MCs comprised of individual nano-sized building blocks often demonstrate close-to-monocrystal structures and corresponding functional properties. Regarding these non-trivial superstructures it is critical to use exotic time-consuming techniques to make a true step forward in understanding MC formation processes in particularly the dynamics of crystallization or MC to MC transformation. In this work we have generated NH4TiOF3 MCs using PEGs (PEG6000, PEG 400) and Brijs (Brij58, BrijC10, BrijS100). We shed light on the formation of anatase mesocrystals and demonstrate how the Ti-PEO chain interactions serve to direct the crystallisation process. A model was developed for the MC formation process via the ratio of Ti atoms to polymer-chain enabled. This model allows for the effect of PEG or Brij@ concentration on the resultant MC morphology was rationalized empirically. Moreover, the photocatalytic activity observed for the TiO2 MCs indicates the polymer does promote 001 facet formation