diff --git a/src/fqe/_fqe_control.py b/src/fqe/_fqe_control.py
index 53e816f..208682a 100755
--- a/src/fqe/_fqe_control.py
+++ b/src/fqe/_fqe_control.py
@@ -446,7 +446,9 @@ def get_restricted_hamiltonian(
     """Initialize spin conserving spin restricted hamiltonian
 
     Args:
-        tensors (Tuple[numpy.ndarray, ...]) - tensors for the Hamiltonian elements
+        tensors (Tuple[numpy.ndarray, ...]) - tensors for the Hamiltonian elements. \
+            Note that the tensor should be in a spin-free form; therefore, \
+            the size of each dimension is the number of spatial orbitals.
 
         e_0 (complex) - scalar part of the Hamiltonian
     """
diff --git a/src/fqe/hamiltonians/restricted_hamiltonian.py b/src/fqe/hamiltonians/restricted_hamiltonian.py
index 9c344b5..f0a61e7 100644
--- a/src/fqe/hamiltonians/restricted_hamiltonian.py
+++ b/src/fqe/hamiltonians/restricted_hamiltonian.py
@@ -34,9 +34,10 @@ def __init__(self,
         Arguments:
             tensors: Variable length tuple containg between one and four
                      numpy.arrays of increasing rank. The tensors contain the
-                     n-body hamiltonian elements. Tensors up to the highest
-                     order must be included even if the lower terms are full of
-                     zeros.
+                     n-body hamiltonian elements in the spin-free form.
+                     Therefore, the size of each dimension is the number of
+                     spatial orbitals.  Tensors up to the highest order must be
+                     included even if the lower terms are full of zeros.
             e_0: Scalar potential associated with the Hamiltonian.
         """
         super().__init__(e_0=e_0)