The binary compound 12CaO·7Al2O3 (C12A7) in the CaO–Al2O3 system was synthesized as a thin film via the sol–gel drop casting method on MgO ⟨1 0 0⟩ single crystal substrates. The resulting films were subjected to heat treatment at different temperatures ranging from 700 to 1200 °C and then comprehensive surface morphology, structural and elemental studies were carried out. Initial signs of the crystallization of the C12A7 thin film was observed at 800 °C and the complete crystallization was achieved on heat treatment at 1100 °C for 3 h.

Spun films of liquid crystalline peripheral-tetrasubstituted zinc (II) phthalocyanine (Pc) derivatives have been employed as active organic semiconducting layers in the fabrication of organic field effect transistors. The Pc molecules in the thin film formulation are stacked perpendicular to the substrate. Values of 1.8×10−4 cm2 V−1 s−1 and 103 were estimated for the field-effect mobility and on/off ratio, respectively, from the hysteresis-free transistor characteristics. The transistor can be switched on and off at a relatively low value of 3.7 V for threshold voltage. The carrier transport is believed to be largely determined by the multidomain Pc film structure.

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In-situ High Temperature X-Ray Diffraction (HTXRD) and Differential Scanning Calorimetric (DSC) studies were performed on a sol-gel derived binary compound of a calcia-alumina (C12A7) system consisting of calcium oxide (CaO) and aluminum oxide (Al 2 O 3) in a ratio of 12:7 for in-situ investigation into the phase transformations under progressively increasing thermal activation from room-temperature to 1200°C. The crystallisation of amorphous samples formulated at room-temperature on magnesium oxide (MgO) single crystal (100) substrates was found to be complete on heat treatment at 1100°C for 3 hours. This observation was further supported by independent Fourier Transform Infrared (FTIR) and Raman Spectroscopies. Values of 348 kJ/mol and 375 kJ/mol were estimated from Kissinger plots for activation energies of crystallisation of CaO and Al 2 O 3 constituents, respectively.

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