The activity of different representative templating molecules along with zeolite framework is investigated using a range of reactivity indexes using density functional theory (DFT), From the values of local softness and the charge on the hydrogen atom of the bridging hydroxyl, resulting from the presence of aluminum in the framework, it is observed that the acidities of the aluminum containing zeolite type model systems are dependent on several characteristics which are of importance within the framework of hard and soft acids and bases (HSAB) principle. We investigated the local softness of the interacting templates to compare their affinity with the zeolite framework cluster models. The cluster models are chosen to mimic the secondary building units of zeolite crystals for both silicalite and silica aluminates. The conformational flexibility was brought out as common features of those representative organic templates. The influence of the nature of the functional group and alkyl group on the electronic interaction is studied systematically. An a priori rule is formulated to choose the best template for a particular zeolite (e.g., ZSM-5) synthesis. The role of water during nucleation process is monitored in terms of solvation energy to rationalize the fundamental mechanism of crystal growth.