About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Materials Processing Fundamentals
|
Presentation Title |
Multiple Crystallization Pathways on Highly Supersaturated Aqueous Solutions |
Author(s) |
Yong Chan Cho, Geun Woo Lee, Sooheyong Lee, Yun-Hee Lee |
On-Site Speaker (Planned) |
Yong Chan Cho |
Abstract Scope |
In supersaturated aqueous solutions, measurements of solution structure and its evolution can provide a key information for characteristic nucleation pathways. We present the structural evolution of dihydrogen phosphate (H2PO4) molecules in extremely supersaturated solutions (KH2PO4 (KDP) and NH4H2PO4 (ADP)) beyond metastable zone width limit. The combination of electrostatic levitation system, in-situ synchrotron X-ray diffraction and in-situ micro-Raman spectroscopy revealed molecular symmetry changes of H2PO4 in highly supersaturated KDP solution indicating the existence of clear solution-solution transition depending on the number of solvent (water) molecules. However, ADP solutions show with a well-developed medium range ordering which is different from those of KDP solution. Our result suggest that changes in short range and medium range order structures in solutions ultimately determines the route of nucleation and phase selection. This work can provide an important insight for understanding of various nucleation phenomena in molecule-level. |
Proceedings Inclusion? |
Planned: |