The exchange coupling J of Co

[xiaolei ma]

Dear developer,

I run the curie-temperature example in the tests file of vampire v5.0.0, the exchange interaction energy J of Co is 1.12e-20J, however, the paper(J. Phys.: Condens. Matter 26 (2014) 103202) show the J of Co is  6.064*10-21J, how to understand this difference?

The simulation results are shown below when using the different J respectively.  It seems the Tc is correct when the J equals 1.12e-20J.

Thank you in advance.

Best regards,

Xiaolei Ma

[milton...@gmail.com]

In the input file of the Co curie-temperature example it says "sc" for simple cubic. Simple cubic has half the coordination number of hcp so J needs to be twice as large to get the same Tc, 6.064e-21 x 2 = 12.128e-21. This isn't quite 11.2e-21 but another number that changes is the "Spin-wave MF correction". I'm guessing these are the reasons.