added relaxed fper benchmark

misc/benchmarks/slb_2024_benchmarks.py

@@ -2,6 +2,7 @@
 
 from burnman import Composite, equilibrate, RelaxedSolution
 from burnman.tools.eos import check_eos_consistency
+from burnman.tools.unitcell import molar_volume_from_unit_cell_volume
 from burnman.minerals import SLB_2024
 
 import numpy as np
@@ -14,6 +15,40 @@
 
 check_eos_consistency(fe_bcc, verbose=True)
 
+fper = RelaxedSolution(
+    SLB_2024.ferropericlase(),
+    [[0.0, 0.5, -0.5, 0.0, 0.0]],
+    [
+        [1.0, 0.0, 0.0, 0.0, 0.0],
+        [0.0, 0.5, 0.5, 0.0, 0.0],
+        [0.0, 0.0, 0.0, 1.0, 0.0],
+        [0.0, 0.0, 0.0, 0.0, 1.0],
+    ],
+)
+
+c = molar_volume_from_unit_cell_volume(1.0, SLB_2024.periclase().params["Z"])
+
+pressures = np.linspace(1.0e5, 140.0e9, 141)
+temperatures = pressures * 0.0 + 300.0
+
+fig = plt.figure(figsize=(10, 5))
+ax = [fig.add_subplot(1, 2, i) for i in range(1, 3)]
+
+fig1 = mpimg.imread("figures/SLB_2024_fper_V.png")
+fig2 = mpimg.imread("figures/SLB_2024_fper_K_T.png")
+ax[0].imshow(fig1, extent=[0.0, 140.0, 50.0, 80.0], aspect="auto")
+ax[1].imshow(fig2, extent=[0.0, 140.0, 100.0, 700.0], aspect="auto")
+
+for x_fe in [0.1, 0.3, 0.5, 1.0]:
+    fper.set_composition([1.0 - x_fe, x_fe, 0.0, 0.0])
+    Vs, K_Ss = fper.evaluate(["V", "K_S"], pressures, temperatures)
+
+    ax[0].plot(pressures / 1.0e9, Vs / c, linestyle=":", linewidth=3.0)
+    ax[1].plot(pressures / 1.0e9, K_Ss / 1.0e9, linestyle=":", linewidth=3.0)
+
+ax[0].set_ylim(50.0, 80.0)
+ax[1].set_ylim(100.0, 700.0)
+plt.show()
 
 temperatures = np.linspace(1.0, 2000.0, 101)
 pressures = temperatures * 0.0 + 1.0e5