Search for the Ground State of Cerous Magnesium Nitrate by an Extended Luttinger-Tisza Method

The ground state of cerous magnesium nitrate is determined using the assumptions that the spins are coupled by purely dipolar forces, the magnetic structure is periodic after eight or less lattice periods, and the spins can be considered as classical vectors. The ground state has a layered antiferromagnetic structure as described in the text. A study is made to see whether this result is dependent on the assumption that the $g$ factor parallel to the crystallographic $c$ axis is zero or almost zero for this specific salt. The conclusion is that this is to a large extent not the case. The ground state lies at an energy - 1.867 mdeg K, using the lattice constants as given by Schiferl.