Energy and specific heat for J=7/2 magnetic crystals

Complementary data for the manuscript "Specific heat of Gd3+  and Eu2+ -based magnetic compounds" by D.J. Garcia, J. Sereni and A.A. Aligia.

We include the energy and specific heat for many magnetic lattices. The magnetic moment is S=7/2. Interactions are taken as Heisenberg-like

H = Sum_{i,\delta}  J_\delta S_i S_{i+\delta}

and \delta is taken to consider first, second, and possibly more nearest neighbors.

Interactions are either all FM or AF to keep the system non-frustrated. We take all |J_\delta|=1K.

Computations are performed using quantum Monte Carlo (QMC) simulations from the ALPS libraries (“dirloop_sse” package) [1, 2]. Calculations are done using 20^3 conventional unit cells.

Files name convention is as follows:

{Lattice Name}_{magnetic order}({number of neighbors})_l_{size of the linear length}

Lattice names are BCC, Diamond, FCC, HCP, and SC  with their classic meaning of Body-Centered Cubic, Face-centered cubic, Hexagonal close-packed, and simple cubic.

LHc corresponds to a layered honeycomb lattice with three NN within the plane of the honeycomb layer and one above or below the layer in alternating sites.

"MgCuAl2" corresponds to the lattice of that compound where Mg has been replaced by a J=7/2 moment.

magnetic order is either ferromagnetic (FM) or antiferromagnetic (AF).

number of neighbors is computed by increasing the considered neighbor radius. Only for the simple cubic case, SC(14), we considered a scenario including the 8 nearest neighbors (NN) and the 6 third NN.

The file SpecificHeatAndEnergy.tgz contains the raw data for all lattices in txt format.

Finite size effects are almost negligible in these cases except for the antiferromagnetic simple cubic lattice ( SC_AF(6) ).

[1] A. Albuquerque, F. Alet, P. Corboz, P. Dayal, A. Feiguin, S. Fuchs, L. Gamper, E. Gull, S. Gürtler, A. Honecker, R. Igarashi, M. Körner et al., The ALPS project release 1.3: Open- source software for strongly correlated systems, Journal of Magnetism and Magnetic Materials 310(2, Part 2), 1187 (2007), doi:https://doi.org/10.1016/j.jmmm.2006.10.304, Proceedings of the 17th International Conference on Magnetism. 

[2] B. Bauer, L. D. Carr, H. G. Evertz, A. Feiguin, J. Freire, S. Fuchs, L. Gamper, J. Gukelberger, E. Gull, S. Guertler, A. Hehn, R. Igarashi et al., The ALPS project release 2.0: open source software for strongly correlated systems, Journal of Statistical Mechanics: Theory and Experiment 2011(05), P05001 (2011), doi:10.1088/1742-5468/2011/05/P05001.