Phase Transition of Layered Manganese Compound: Mn(NH₃)₂Ni(CN)₄2C₁₂H₁₀

Abstract

The magnetic susceptibility and the heat capacity of a layered manganese compound Mn(NH₃)₂Ni(CN)₄2C₁₂H₁₀ have been measured down to the temperature, T=0.5 T_N. A symmetric logarithmic singularity of heat capacity, which was found for isomorphic nickel compound Ni(NH₃)₂Ni(CN)₄2C₁₂H₁₀ at T_N=0.800±0.005 K has been observed, in this case, at T_N=0.172±0.001 K. The singularity of magnetic susceptibility at T_N is consistent with that of heat capacity.