| 报告题目 | Transition Metal Compounds in Extreme Environments |
| 报告人 | 林俊孚 教授 |
| 报告人单位 | Department of Geological Sciences, Jackson School of Geosciences. The University of Texas at Austin |
| 报告时间 | 2014-07-09 |
| 报告地点 | 合肥微尺度物质科学国家实验室九楼会议室 |
| 主办单位 | 合肥微尺度物质科学国家实验室 |
| 报告介绍 | 报告摘要：
Transition metals (TM) with partially-filled d electron shells form a series of compounds with a uniquely wide range of electronic, magnetic, elastic, and thermodynamic properties. These compounds can have a plethora of implications in electronics, semiconductors, optical switches, resistors, magnetic devices, superconductors, to name a few. The discovery of 2-dimensional (2D) mono-layered and multi-layered TM dichalcogenides (TMDs), such as MoS2, opens the window for technological impacts of 2D TMDs including intelligent clothing, medical diagnostics, energy harvesters, tunable materials, energy storage, personal care, and flexible electronics. These TMDs are comprised of stacked quasi-two-dimensional sheets of metal atoms covalently bonded with two sheets of chalcogen atoms above and below them. It has recently been found that there is a whole host of 2D materials with interesting and special properties. Studying the electronic, magnetic, elastic, vibrational, and structural properties of 2D/3D TM compounds in extreme pressures and temperatures is thus of great research interest in materials science and condensed matter physics. As a result of the partially-filled d electronic orbitals, however, the TM compounds can exhibit complex behaviors that are challenging to unveil.
Here I will present recent research results on TM compounds using magnetite, “122” iron pnictides, and 2D MoS2 as examples to illustrate the interplays between their electronic, magnetic, and structural properties at high pressures and low temperatures. I will use these examples to highlight recent technical advances in synchrotron-based inelastic X-ray scattering and laser spectroscopies coupled with diamond anvil cells that have offered a plethora of research opportunities at extreme P-T environments. These studies unleash new insights into phonon dispersion curves, phonon density of states, electronic structures (e.g., spin and valence states), magnetism, elasticity, metallization and band gaps, as well as bonding characters of the representative TM compounds. Implications in materials science and condensed matter physics as well as future challenges and research opportunities will also be addressed so as to stimulate participating scientists in the community to explore this new frontier research in TM compounds collaboratively. |
