The origin of the G-type antiferromagnetism (AFM(G)) and puzzling properties of RTiO3 with R=La are studied. We clarify that the crystal field from La caused by the GdFeO3-type distortion lifts the t2g degeneracy at Ti 3d orbitals. The lift stabilizes the AFM(G) with spin-exchange constant in agreement with neutron scattering results. The orbital-spin structures for R=Pr, Nd and Sm are also consistent with experiments. We propose that the GdFeO3-type distortion has a universal mechanism of controlling orbital-spin structure competing with the Jahn-Teller (JT) mechanism.
@article{arxiv.cond-mat/0301049,
title = {Orbital-Spin Structure and Coupling to Lattice in RTiO$_3$ with R=La,Pr,Nd and Sm},
author = {Masahito Mochizuki and Masatoshi Imada},
journal= {arXiv preprint arXiv:cond-mat/0301049},
year = {2007}
}