000			02964nam a22001697a 4500
999			_c21988 _d21988
005			20230124161126.0
008			230124b ||||| |||| 00| 0 eng d
020			_ahbk
082			_a547.2 _bSy78
100			_aSikander Hayat, _bMS (Chemistry), _c2016-2018, _dDr. Muhammad Adnan Asghar
245			_aSynthesis and characterization of inorganic-organic hybrid phase change crystals _c/ Sikander Hayat
260			_aD.G Khan : _bUniversity of Education, Department of Chemistry, _c2018
300			_a70 p. _eCD
520			_aAmong phase change crystals (PCCs), solid to solid reversible phase change crystals have been considered very imperative crystals. Since last decades these crystals have wide applications in dielectrics, signal processing, non linear optics (optoelectronic), ferroelectric, piezoelectric, sensing, and data storage gadgets/devices. Subsequently, phase change crystals (PCCs) have earned vital attention in impacting the technology. Inorganic-organic hybrid phase change crystals have been synthesized by selecting possible flexible amine with transition metal halides such as CuCl2 and ZnCl2. These combinations reactions resulted in the construction of new crystals possessing the properties of differential scanning calomerty and switchable dielectrics at (Tc) phase change point. In the present research work two new below room temperature crystals with considerable switchable dielectrics and phase change properties are synthesized. These compounds are; [(C6H14) NH2]2 • CuBr4 (1) and [(C6H14) NH2]2 • ZnBr4 (2). The compound [(C6H14) NH2]2 • ZnBr4 (2) exhibits admirable dielectric switching properties in the temperature range of 220 K to 245 K, justifying that this crystal has distinct dielectric states below and above Tc (233 K). The characterization of the above said hybrid crystals were done by using different techniques such as, differential scanning calorimetry (for the exact prediction of Tc), thermal gravimetric analysis (melting point), and single X-ray crystal diffraction analysis (structural and mechanistic studies), powder X-ray diffraction analysis (phase purity of samples) and dielectric measurements. The major driving force of phase change is believed to be due to the order-disorder of terminal carbon atom of short limb (ethyl group) of n-butyl-ethyl amine cation along with reorientation movements in ZnBr4 anion. Moreover, the deuterated analogue of 2 was also subjected to DSC (Differential Scanning Calorimetry) to check the involvement of proton dynamic movements in phase change behavior. It has been observed that a little shifting of peaks during analysis of deuterated sample of 2 is the sign of contribution of proton dynamic motions in phase change phenomenon. It is considered that this strategy and findings will be supportive for the searching of novel phase change crystals with valuable switching properties.
650			_aChemistry--Synthesis--Characterization--Crystals
942			_cTH