Thermodynamic properties and structural geometry of KMgCl3·6H2O single crystals



Yoon, Hyo In;Lim, Ae Ran

  • 투고 : 2015.11.13
  • 심사 : 2015.12.10
  • 발행 : 2015.12.20


The thermodynamic properties and structural geometry of $KMgCl_3{\cdot}6H_2O$ were investigated using thermogravimetric analysis, differential scanning calorimetry, and nuclear magnetic resonance. The initial mass loss occurs around 351 K ($=T_d$), which is interpreted as the onset of partial thermal decomposition. Phase transition temperatures were found at 435 K ($=T_{C1}$) and 481 K ($=T_{C2}$). The temperature dependences of the spin-lattice relaxation time $T_1$ for the $^1H$ nucleus changes abruptly near $T_{C1}$. These changes are associated with changes in the geometry of the arrangement of octahedral water molecules.


$KMgCl_3{\cdot}6H_2O$;Thermodynamic property;Nuclear magnetic resonance;Phase transition


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연구 과제 주관 기관 : National Research Foundation of Korea (NRF)