Hyperfine interactions in Gd2Ti2O7 pyrochlore

Abstract

The cubic pyrochlore structure of the RE2Ti2O7 (R= rare earth) form is highly geometrically frustrated antiferromagnets and Gd2Ti2O7 is particularly interesting due to the fact gadolinium has a large magnetic moment and its orbital momentum is zero. Up to nowadays, a few investigations of the local structure on Gd2Ti2O7 using hyperfine interactions techniques were made. Namely, the magnetic hyperfine interaction at Gd previously reported from Mossbauer effect spectroscopy with 155Gd [1] and perturbed angular correlation (PAC) have used to reach electric field gradient at 111mCd and 111In probe nuclei [2]. However, these studies are lacking in interpretation, so first principles calculations may led to the elucidation of the electronic structure at the specific crystalline site. Then, Gd2Ti2O7 single and doped-Cd cell simulations have performed with full potential linearized augmented plane waves methods and generalized gradient approximation from Perdew-Burke-Ernzerhorf within the WIEN2k code. Electric field gradient and magnetic hyperfine components were evaluated.