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How to add external magnetic field in Dalton

Posted: 24 Dec 2015, 02:38
by Yanxh
I have the FeGa alloy which is a Giant magnetostrictive material. I want to make some calculations about the elastic constants( such as C11,C12,C33 etc) for FeGa alloy with external magnetic field怂
I also want to calculate the magnetic conductivity态Magnetostrictive coefficient. Can Dalton do that ?

Re: How to add external magnetic field in Dalton

Posted: 25 Dec 2015, 18:41
by taylor
Your question is so short it is very difficult to know how to respond. Are you saying that (e.g.) the magnetic properties already available in Dalton are inadequate for your purpose? If so, how? What do you mean by "elastic constants"? If you mean the vibrational modes of a molecule, then this can be handled within Dalton. However, such terminology usually refers to vibrations in solid/periodic systems, which are outside the scope of a molecular program like Dalton.

Application of an explicit external magnetic field, that is, including it in the Hamiltonian of the system, results in a complex wave function and optimization thereof. In Dalton magnetic fields are treated by response theory, and are thus handled as small perturbations to the system. This allows one to sidestep the complex calculation and instead to look at the response of the initial wave function (SCF, DFT, MCSCF, CC) to the applied small perturbation. If you are interested in strong magnetic fields, for which perturbation theory would be inadequate, this is not available in Dalton. The Oslo group (Erik Tellgren, Trygve Helgaker) has a code which can treat an explicit magnetic field of arbitrary strength, but this code is not generally available. You can try to contact them for more assistance if this is your interest.

Best regards