1. 연수기간 : 2021. 11. 21 ~ 2021. 11. 25 (총 4박 5일)
2. 연수국가 : 온라인 진행
3. 연수기관명 : KVS (The Korean Vacuum Society)
4. 연수자 : 석박사통합과정 7기 참여대학원생 1명
5. 연수주제 : Compressional Behavior of Potassium Hydrides Using X-ray and Raman Spectroscopic
Hydrogen-rich materials with high phonon frequency are considered strong candidates exhibiti nghigh transiti on temperature of superconducti vity (Tc). For instance, ab initi o calculati on for KH6 predicted superconducti vity of 58.6 K to 69.8 K at 166GPa [Zhou et al., 2012]. The eff orts arecurrently underway to increase the correlati on between experiments and predicti ons. We investi gated the structural properti es of potassium under hydrogen up to 70 GPa in diamondanvil cells by using synchrotron X-ray diff racti on (XRD) and micro-confocal Raman spectroscopy.Our results of the synchrotron XRD data have revealed that in additi on to the potassiummonohydrides (KH) phase, a Cmcm phase formed at 10 GPa and persisted unti l 70 GPa. Theresults of pressure-induced Raman spectra also suggested the formati on of a new phase at 10GPa. We observed an additi onal stretching mode of hydrogen near the vibrati on frequency (4229cm-1) of the initi al bulk hydrogen (4213 cm-1), which may indicate the formati on of the Cmcmphase. Additi onally, the full width at half maximum of initi al bulk hydrogen decreased at 10 GPa,suggesti ng the decrease of the intermolecular interacti on. Studies on Raman vibrati onal modes inthe potassium hydrides system are underway to understand the nature of the vibrati onalproperti es of the alkali metals at high pressure of hydrogen. Our results will allow us to designand develop alternati ve routes to synthesize the novel materials and understand thesuperconducti vity of potassium polyhydrides.