Synthesis and characterization of inorganic-organic hybrid phase change crystals (Record no. 21988)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 02964nam a22001697a 4500 |
| 005 - DATE AND TIME OF LATEST TRANSACTION | |
| control field | 20230124161126.0 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION | |
| fixed length control field | 230124b ||||| |||| 00| 0 eng d |
| 020 ## - INTERNATIONAL STANDARD BOOK NUMBER | |
| International Standard Book Number | hbk |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 547.2 |
| Item number | Sy78 |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Student name | Sikander Hayat, |
| Class | MS (Chemistry), |
| Session | 2016-2018, |
| Supervisor | Dr. Muhammad Adnan Asghar |
| 245 ## - TITLE STATEMENT | |
| Title | Synthesis and characterization of inorganic-organic hybrid phase change crystals |
| Statement of responsibility, etc | / Sikander Hayat |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc | D.G Khan : |
| Name of publisher, distributor, etc | University of Education, Department of Chemistry, |
| Date of publication, distribution, etc | 2018 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 70 p. |
| Accompanying material | CD |
| 520 ## - SUMMARY, ETC. | |
| Summary, etc | Among 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 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Chemistry--Synthesis--Characterization--Crystals |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Koha item type | Theses |
| Withdrawn status | Damaged status | Home library | Current library | Date acquired | Full call number | Barcode | Date last seen | Price effective from | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| UE-Central Library | UE-Central Library | 24.01.2023 | 547.2 Sy78 | TTH252 | 24.01.2023 | 24.01.2023 | Theses |
