unit conversion

[XBob]

Hi all，I have always used Mumax3 for micromagnetic simulations, but recently I have switched to a different simulation software, which is Spirit Web.In Mumax, what are the conversion factors for the units of Ms(A·m−1), A(J·m−1), K(J·m−3), and D(J·m−2) to the units of Spirit? In "spirit", Ms used a number, which can be either 1.0 or 2.0. and K used "meV", while A and D used "meV/unique pair".And in the description provided by Spirit for K and D, it mentions "number of shells". What exactly are these "shells"? I will be grateful if you please let me know how to solve this problem. 

[Антон Луценко]

Hi,

Spirit seems to be atomistic simulator (and therefore utilizes units related to single atoms), while Mumax3 uses continuous approximation (and uses bulk material properties). While there is a relation between the units, your questions relate more to the quantum theory of magnetism rather than to the usage of Mumax3.