Journal of the Korean Magnetic Resonance Society (한국자기공명학회논문지)

Korean Magnetic Resonance Society (한국자기공명학회)
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Thermodynamic properties and structural geometry of KMgCl3·6H2O single crystals

  • Yoon, Hyo In (Department of Science Education, Jeonju University) ;
  • Lim, Ae Ran (Department of Science Education, Jeonju University)
  • Received : 2015.11.13
  • Accepted : 2015.12.10
  • Published : 2015.12.20
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Abstract

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.

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References

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