We present a first-principles investigation of the spin-ice state in Dy2Ti2O7 using a magnetic source-free exchange and correlation functional, implemented in the CASTEP electronic-structure code. By comparing results from the conventional local spin-density approximation, we show that a spin-ice state in Dy2Ti2O7 can be reliably obtained by removing the magnetic sources from the exchange and correlation contributions to the potential, and we contrast this against the computed ground states of other frustrated pyrochlore magnets.
HAWKHEAD et al. (Mon,) studied this question.