[Pw_forum] Doubt in Curie temperature value

[Padmaja Patnaik]

Hi

I am calculating the Curie Temperature for Iron. The experimental value for this is  1043 K. I am getting the value as 2398.97 K. I am using the following way to calculate.
Find out the ferromagnetic and anti-ferromagnetic energy of Fe. The difference between these two gives the value of J_0. Then,
T_c = [2/3] [J_0/K_B]

Please suggest me what is wrong? Why am I getting such a high value. On the other hand I am getting very low value for Ni, whose experimental Curie temperature is 627K and I am getting 315K. 
Thanking you in advance,
regards
Padmaja Patnaik

Research Scholar

Dept of Physics

IIT Bombay

Mumbai, India


      
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