add metadata to model card

README.md

@@ -5,6 +5,24 @@ language:
 tags:
 - science
 - physics
+metadata:
+  parameterization: "slab"
+  number_of_layers: 2
+  param_ranges:
+    thicknesses: [1., 1500.]
+    roughnesses: [0., 60.]
+    slds: [-8., 16.]
+    r_scale: [0.9, 1.1]
+    log10_background: [-10.0, -4.0]
+  bound_width_ranges:
+    thicknesses: [1.0e-2, 1500.]
+    roughnesses: [1.0e-2, 60.]
+    slds: [1.0e-2, 5.]
+    r_scale: [1.0e-3, 0.2]
+    log10_background: [1.0e-2, 6.0]
+  shift_param_config:
+    r_scale: true
+    log10_background: true
 ---
 
 # Model Card for `neutrons-2layers-basic-v1`