Data for Control of the third dimension in copper-based square-lattice antiferromagnets

Despite the structural motifs common to this family and Cu(pyz)2(ClO4)2, the latter has significantly stronger two-dimensional exchange interactions and hence a higher ordering temperature. We discuss these results, as well as the mechanisms that might drive the long-range order in these materials, in terms of departures from the ideal S=1/2 two-dimensional square-lattice Heisenberg antiferromagnet. In particular, we find that both spin-exchange anisotropy in the intralayer interaction and interlayer couplings (exchange, dipolar, or both) are needed to account for the observed ordering temperatures, with the intralayer anisotropy becoming more important as the layers are pulled further apart.<br><br>Figure 4, panel (a) hf2_0_41k.dat (black points) hf2_0_41k.tab (black line) pyo_0_1k.dat (red points) pyo_0_1K.tab (red line) phpy_0_26k.dat (green points) phpy_0_26k.fit (green line) clo4_0_34k.dat (blue points) clo4_0_34k.tab (blue line) Figure 4, panel (b) hf2_freq.dat (black points): columns 1,5,6 pyo_freq.dat (red points): columns 3,17,18 phpy_freq.dat (green points): columns 1,3,4 clo4_freq.dat (blue points): columns 1,5,6