About the event
Physical Chemistry Seminar – Zoom Only
Sohan Ahmed (Yoo Group)
Title: Dynamics of the melting and phase transition of nitrogen
Abstract: Nitrogen is an interesting material exhibiting molecular and polymer like behavior as well as melt maximum at high temperatures. At very high pressure, nitrogen forms an amorphous phase with a nonmolecular semiconductor characteristics. Studies of the high temperature and high pressure melt of nitrogen by Raman and Synchrotron x-ray diffraction are reviewed. Raman study of the nitrogen melt is reviewed from a pressure range of 25 GPa to 103 GPa and temperature from 300 to 2000 K. The solid-liquid phase boundary has been probed with a time resolved Raman spectroscopy on ramp heated nitrogen in Diamond Anvil Cell (DAC). The solid-solid phase boundaries have been measured with spatially resolved micro-confocal Raman spectroscopy on resistively heated DAC, probing the δ-ε phase line. Synchrotron x-ray diffraction measurements of nitrogen are reviewed up to 120 GPa to determine the melting curve and the
structural changes of the solid and liquid phases along it. Also, a first order liquid-liquid phase transition above 50 GPa is reviewed. Based on these reviews a research goal is hypothesized.
Meeting ID: 938 0915 3065