투고논문


JKMRS Volume 26, No 1, pp 10, Investigation on structural symm...
2022년 03월 20일 / 조회수: 344
Investigation on structural symmetry of CsCoCl3·2H2O crystals by magic-angle spinning 1H and static 133Cs nuclear magnetic resonance


Sang Hyeon Park,1 Du Chang Jang,1 Hara Jeon,1 Oh Yi Gyeong,1 Ae Ran Lim1, 2, *


1Graduate School of Carbon Convergence Engineering, Jeonju University, Jeonju 55069, Republic of Korea
2Department of Science Education, Jeonju University, Jeonju 55069, Republic of Korea 




Received Mar 14, 2022; Revised Mar 18, 2022; Accepted Mar 19, 2022

 
Abstract: The phase transition temperatures of CsCoCl3·2H2O crystals are investigated via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Three endothermic peaks at temperatures of 370 K (=TC1), 390 K (=TC2), and 416 K (=TC3) were observed for phase transitions from CsCoCl3·2H2O to CsCoCl3· 1.5H2O, to CsCoCl3·H2O, and then to CsCoCl3· 0.5H2O, respectively. In addition, the spin-lattice relaxation time T1ρ in the rotating frame and T1 in the laboratory frame as well as changes in chemical shifts for 1H and 133Cs near TC1 were found to be temperature dependent. Our analyses results indicated that the changes of chemical shifts, T1ρ, and T1 are associated with structural phase transitions near temperature TC1. The changes of chemical shifts, T1ρ, and T1 near TC1 were associated with structural phase transitions, owing to the changes in the symmetry of the structure formed of H2O and Cs+ ions. Consequently, the structural symmetry in CsCoCl3·2H2O crystals based on temperature is discussed by the environments of their H and Cs nuclei.

Keywords: CsCoCl3·2H2O, spin-lattice relaxation time, thermal property, nuclear magnetic resonance

* Address correspondence to: Ae Ran Lim, Graduate School of Carbon Convergence Engineering, and Department of Science Education, Jeonju University, Jeonju 55069, Republic of Korea, Tel: 82-63-220-2514; E-mail: arlim@jj.ac.kr
첨부파일 2_ARLim.pdf