diff --git a/Doc/FFCatalog/fig/ff2/bornplot.py b/Doc/FFCatalog/fig/ff2/bornplot.py
index e6c4e4242eb55f050c50247fbee4c33fd931161c..df86cc93e2d1a9f510a49ff50ab2aa0bbddae0d2 100644
--- a/Doc/FFCatalog/fig/ff2/bornplot.py
+++ b/Doc/FFCatalog/fig/ff2/bornplot.py
@@ -10,7 +10,7 @@ rc('text', usetex=True)
 rc('image', cmap='inferno')
 
 import bornagain as ba
-from bornagain import nanometer, degree, angstrom, deg2rad
+from bornagain import nm, degree, angstrom, deg2rad
 
 
 class BinRange:
diff --git a/Doc/FFCatalog/fig/ff2/sim_AnisoPyramid.py b/Doc/FFCatalog/fig/ff2/sim_AnisoPyramid.py
index f16612fd6252f0c31b5832a088091a3cd03e9c19..64d2649e6149afd74b86002f24ddf5f319528bc5 100644
--- a/Doc/FFCatalog/fig/ff2/sim_AnisoPyramid.py
+++ b/Doc/FFCatalog/fig/ff2/sim_AnisoPyramid.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorAnisoPyramid(13*nanometer, 8*nanometer, 4.2*nanometer,
+    ff = ba.FormFactorAnisoPyramid(13*nm, 8*nm, 4.2*nm,
                                    60.0*degree)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
diff --git a/Doc/FFCatalog/fig/ff2/sim_Box.py b/Doc/FFCatalog/fig/ff2/sim_Box.py
index c93f4c1dd3e56ca1b569699bfc3b185f3b2b8951..a29492cbb8ffec3106bb6df53fdd727ce879b49b 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Box.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Box.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorBox(18*nanometer, 4.6*nanometer, 3*nanometer)
+    ff = ba.FormFactorBox(18*nm, 4.6*nm, 3*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_CantellatedCube.py b/Doc/FFCatalog/fig/ff2/sim_CantellatedCube.py
index bb29d4db3a488a49aba439e60952f31a5bb943eb..0450528a9a808d93beb5b037466bb79f5364462a 100644
--- a/Doc/FFCatalog/fig/ff2/sim_CantellatedCube.py
+++ b/Doc/FFCatalog/fig/ff2/sim_CantellatedCube.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 45*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorTruncatedCube(6.4*nanometer, 1.5*nanometer)
+    ff = ba.FormFactorTruncatedCube(6.4*nm, 1.5*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Cone.py b/Doc/FFCatalog/fig/ff2/sim_Cone.py
index b643a7d58828e7dc8443b3b8f7e182e175394825..cc428c8f68719384f3110a31752a70f258ee1c97 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Cone.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Cone.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     theta = 30*i/(n - 1)
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorCone(4*nanometer, 11*nanometer, 75*degree)
+    ff = ba.FormFactorCone(4*nm, 11*nm, 75*degree)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Cone6.py b/Doc/FFCatalog/fig/ff2/sim_Cone6.py
index 8af159a9fb4d5b041422907e234e67a1fb0c2228..ef82768f9a51e97783d9137a15cb41d6dd90bafe 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Cone6.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Cone6.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 30*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorCone6(6*nanometer, 5*nanometer, 60*degree)
+    ff = ba.FormFactorCone6(6*nm, 5*nm, 60*degree)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_CosineRipple.py b/Doc/FFCatalog/fig/ff2/sim_CosineRipple.py
index 7d60efac67b73b01405f47f84964f1656c248c77..9ad0c759eb0828c188b00ac1b3b7b8f4ddd71dc5 100644
--- a/Doc/FFCatalog/fig/ff2/sim_CosineRipple.py
+++ b/Doc/FFCatalog/fig/ff2/sim_CosineRipple.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorCosineRipple(25*nanometer, 10*nanometer, 8*nanometer)
+    ff = ba.FormFactorCosineRipple(25*nm, 10*nm, 8*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Cuboctahedron.py b/Doc/FFCatalog/fig/ff2/sim_Cuboctahedron.py
index 6b4bef9e992ca9b74ec48df0467d398822a2d3cb..c5c91417267081fd4a21a982d1551385515ba20b 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Cuboctahedron.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Cuboctahedron.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 45*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorCuboctahedron(8*nanometer, 5*nanometer, 0.5, 60.0*degree)
+    ff = ba.FormFactorCuboctahedron(8*nm, 5*nm, 0.5, 60.0*degree)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Cylinder.py b/Doc/FFCatalog/fig/ff2/sim_Cylinder.py
index 685d1334a4266cf736aa5fcfd7239333a942906f..d877b421364dfacb9a9ac542c11efea1cf6f4b0c 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Cylinder.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Cylinder.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, -5, 5, -5, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     theta = 135*i/(n - 1)
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorCylinder(3*nanometer, 8.8*nanometer)
+    ff = ba.FormFactorCylinder(3*nm, 8.8*nm)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_asy.py b/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_asy.py
index 2e027ba870bd16452509167e2daaea8acf4c95e9..621a9a649d889bca22e2ec615194ccee1a54d17d 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_asy.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_asy.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 import math
 
@@ -12,19 +12,19 @@ results = []
 edge = 3.2
 
 title = 'default'
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff)
 results.append(bp.Result(0, data, title))
 
 title = 'rotated'
 trafo = ba.RotationZ(13*degree)
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(1, data, title))
 
 title = 'rotated, tilted'
 trafo = ba.createProduct(ba.RotationX(9*degree), ba.RotationZ(13*degree))
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(2, data, title))
 
diff --git a/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_sym.py b/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_sym.py
index a49a6c1f8a26ff39fdf145f6f90a7fea3e916bc8..3f88c13e8c1ad75deecd2834f5c7d8e843ea43cc 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_sym.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Dodecahedron_sym.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 import math
 
@@ -13,19 +13,19 @@ edge = 3.2
 
 title = 'face normal'
 trafo = ba.RotationY(26.5651*degree)
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(0, data, title))
 
 title = 'vertex normal'
 trafo = ba.RotationY(-52.6226*degree)
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(1, data, title))
 
 title = 'edge normal'
 trafo = ba.RotationY(58.2825*degree)
-ff = ba.FormFactorDodecahedron(edge*nanometer)
+ff = ba.FormFactorDodecahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(2, data, title))
 
diff --git a/Doc/FFCatalog/fig/ff2/sim_EllipsoidalCylinder.py b/Doc/FFCatalog/fig/ff2/sim_EllipsoidalCylinder.py
index 6c06ca92e056321f67323e5265972a42e6016ce4..267a42f7e96a0e21d10fbefd3cf9670db950baa5 100644
--- a/Doc/FFCatalog/fig/ff2/sim_EllipsoidalCylinder.py
+++ b/Doc/FFCatalog/fig/ff2/sim_EllipsoidalCylinder.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorEllipsoidalCylinder(6.3*nanometer, 4.2*nanometer, 3*nanometer)
+    ff = ba.FormFactorEllipsoidalCylinder(6.3*nm, 4.2*nm, 3*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_FullSphere.py b/Doc/FFCatalog/fig/ff2/sim_FullSphere.py
index 8053eaeecf573ae9714ab733cec0030660baff9f..eaf98cef1c9ae3e2de94240203a1e7662d3d4934 100644
--- a/Doc/FFCatalog/fig/ff2/sim_FullSphere.py
+++ b/Doc/FFCatalog/fig/ff2/sim_FullSphere.py
@@ -2,14 +2,14 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
 n = 1
 results = []
 for i in range(n):
-    ff = ba.FormFactorFullSphere(3.9*nanometer)
+    ff = ba.FormFactorFullSphere(3.9*nm)
     data = bp.run_simulation(det, ff)
     results.append(bp.Result(i, data))
 
diff --git a/Doc/FFCatalog/fig/ff2/sim_FullSpheroid.py b/Doc/FFCatalog/fig/ff2/sim_FullSpheroid.py
index 81e92260422794f7ee51106823f811a6e61c85ee..778a9ddbcba9ad56d96b2b861e851257150aa451 100644
--- a/Doc/FFCatalog/fig/ff2/sim_FullSpheroid.py
+++ b/Doc/FFCatalog/fig/ff2/sim_FullSpheroid.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     theta = 90*i/(n - 1)
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorFullSpheroid(3*nanometer, 13*nanometer)
+    ff = ba.FormFactorFullSpheroid(3*nm, 13*nm)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_HemiEllipsoid.py b/Doc/FFCatalog/fig/ff2/sim_HemiEllipsoid.py
index 32c863efb4e0728b5d37acdd43c43f247e031fa5..16d45c97d060aefb1bf14e47f98dcf96c731faed 100644
--- a/Doc/FFCatalog/fig/ff2/sim_HemiEllipsoid.py
+++ b/Doc/FFCatalog/fig/ff2/sim_HemiEllipsoid.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorHemiEllipsoid(10*nanometer, 3.8*nanometer, 3.2*nanometer)
+    ff = ba.FormFactorHemiEllipsoid(10*nm, 3.8*nm, 3.2*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Icosahedron_asy.py b/Doc/FFCatalog/fig/ff2/sim_Icosahedron_asy.py
index 7a6ed55114f4f9a4c9aa587ab4a15ab691bb99bc..fd458cc1e4b9d783ad4077f601d472469b84e1a5 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Icosahedron_asy.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Icosahedron_asy.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 import math
 
@@ -12,19 +12,19 @@ results = []
 edge = 4.8
 
 title = 'default'
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff)
 results.append(bp.Result(0, data, title))
 
 title = 'rotated'
 trafo = ba.RotationZ(13*degree)
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(1, data, title))
 
 title = 'rotated, tilted'
 trafo = ba.createProduct(ba.RotationX(9*degree), ba.RotationZ(13*degree))
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(2, data, title))
 
diff --git a/Doc/FFCatalog/fig/ff2/sim_Icosahedron_sym.py b/Doc/FFCatalog/fig/ff2/sim_Icosahedron_sym.py
index 4447947f3fe9275e6a9d4c9786304277e193bba2..dbd39f00f0870561ff776a0d338f5c1e194b6c77 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Icosahedron_sym.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Icosahedron_sym.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 import math
 
@@ -13,19 +13,19 @@ edge = 4.8
 
 title = 'face normal'
 trafo = ba.RotationY(48.1897*degree)
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(0, data, title))
 
 title = 'vertex normal'
 trafo = ba.RotationY(-52.6226*degree)
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(1, data, title))
 
 title = 'edge normal'
 trafo = ba.RotationY(69.0948*degree)
-ff = ba.FormFactorIcosahedron(edge*nanometer)
+ff = ba.FormFactorIcosahedron(edge*nm)
 data = bp.run_simulation(det, ff, trafo)
 results.append(bp.Result(2, data, title))
 
diff --git a/Doc/FFCatalog/fig/ff2/sim_Prism3.py b/Doc/FFCatalog/fig/ff2/sim_Prism3.py
index 62c5da39d58fb8e2d45639665cbf5f67e9ac5176..e44f2ee9cd94300690f00c6c9521675165b0d019 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Prism3.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Prism3.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 30*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorPrism3(13.8*nanometer, 3*nanometer)
+    ff = ba.FormFactorPrism3(13.8*nm, 3*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Prism6.py b/Doc/FFCatalog/fig/ff2/sim_Prism6.py
index e2401152953d7449902cb02684b618600c62b2f1..97d1f0dc7993b35d0d96d4cbadf977f6edc17714 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Prism6.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Prism6.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 30*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorPrism6(5.7*nanometer, 3*nanometer)
+    ff = ba.FormFactorPrism6(5.7*nm, 3*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Pyramid.py b/Doc/FFCatalog/fig/ff2/sim_Pyramid.py
index 6f4e5667520eb1d823f9e1e167479d50c43bcdc3..03f8e2243b47e302f25ef0d018e3a64b2711bee6 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Pyramid.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Pyramid.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 45*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorPyramid(10*nanometer, 4.2*nanometer, 60.0*degree)
+    ff = ba.FormFactorPyramid(10*nm, 4.2*nm, 60.0*degree)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_SawtoothRipple.py b/Doc/FFCatalog/fig/ff2/sim_SawtoothRipple.py
index 2cf6dcc90e63066bc066e7f48e329fdce20936e5..ef718ef24dceda874801ef4e101570ec9c92d0d2 100644
--- a/Doc/FFCatalog/fig/ff2/sim_SawtoothRipple.py
+++ b/Doc/FFCatalog/fig/ff2/sim_SawtoothRipple.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, -5, 5, -5, 5)
@@ -11,8 +11,8 @@ results = []
 for i in range(n):
     omega = 90*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorSawtoothRippleBox(25*nanometer, 10*nanometer, 8*nanometer,
-                                        5*nanometer)
+    ff = ba.FormFactorSawtoothRippleBox(25*nm, 10*nm, 8*nm,
+                                        5*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_Tetrahedron.py b/Doc/FFCatalog/fig/ff2/sim_Tetrahedron.py
index f4628caeba123a4eebb8c9bda38524ff344d693f..5d1e3e8038cfdfc4ecc52c2a382285ae5e68b1b3 100644
--- a/Doc/FFCatalog/fig/ff2/sim_Tetrahedron.py
+++ b/Doc/FFCatalog/fig/ff2/sim_Tetrahedron.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, -5, 5, -5, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 60*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorTetrahedron(12*nanometer, 8*nanometer, 75*degree)
+    ff = ba.FormFactorTetrahedron(12*nm, 8*nm, 75*degree)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_TruncatedCube.py b/Doc/FFCatalog/fig/ff2/sim_TruncatedCube.py
index bb29d4db3a488a49aba439e60952f31a5bb943eb..0450528a9a808d93beb5b037466bb79f5364462a 100644
--- a/Doc/FFCatalog/fig/ff2/sim_TruncatedCube.py
+++ b/Doc/FFCatalog/fig/ff2/sim_TruncatedCube.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     omega = 45*i/(n - 1)
     title = r'$\omega=%d^\circ$' % omega
-    ff = ba.FormFactorTruncatedCube(6.4*nanometer, 1.5*nanometer)
+    ff = ba.FormFactorTruncatedCube(6.4*nm, 1.5*nm)
     trafo = ba.RotationZ(omega*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_TruncatedSphere.py b/Doc/FFCatalog/fig/ff2/sim_TruncatedSphere.py
index 88638d47fc5ffc134c57eb454921d617090d321b..95d2e31f4eb4ace489069bef19237a8e3231a0e4 100644
--- a/Doc/FFCatalog/fig/ff2/sim_TruncatedSphere.py
+++ b/Doc/FFCatalog/fig/ff2/sim_TruncatedSphere.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     theta = 30*i/(n - 1)
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorTruncatedSphere(4.2*nanometer, 6.1*nanometer, 0)
+    ff = ba.FormFactorTruncatedSphere(4.2*nm, 6.1*nm, 0)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_TruncatedSpheroid.py b/Doc/FFCatalog/fig/ff2/sim_TruncatedSpheroid.py
index f442cd3dee362fa620e55abadd4e6b76bbc833aa..794287a249a562ef7974a451403265010e925434 100644
--- a/Doc/FFCatalog/fig/ff2/sim_TruncatedSpheroid.py
+++ b/Doc/FFCatalog/fig/ff2/sim_TruncatedSpheroid.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -11,7 +11,7 @@ results = []
 for i in range(n):
     theta = 30*i/(n - 1)
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorTruncatedSpheroid(3.3*nanometer, 9.6*nanometer, 1.8, 0)
+    ff = ba.FormFactorTruncatedSpheroid(3.3*nm, 9.6*nm, 1.8, 0)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_demo_1quadrants.py b/Doc/FFCatalog/fig/ff2/sim_demo_1quadrants.py
index 8597bc4ec5de429c2840bac501cc2bf102b0486a..c2218134ac7fe7fe444f69ad3a3ce3d87349a78d 100644
--- a/Doc/FFCatalog/fig/ff2/sim_demo_1quadrants.py
+++ b/Doc/FFCatalog/fig/ff2/sim_demo_1quadrants.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, 0, 5, 0, 5)
@@ -12,7 +12,7 @@ results = []
 for i in range(n):
     theta = pars[i]
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorTruncatedSphere(4.2*nanometer, 6.1*nanometer, 0)
+    ff = ba.FormFactorTruncatedSphere(4.2*nm, 6.1*nm, 0)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_demo_4quadrants.py b/Doc/FFCatalog/fig/ff2/sim_demo_4quadrants.py
index 5f83d65cd26ad8e478848094cc3594dea4143971..454efa727b984ad111f203fc97b0198047897e7d 100644
--- a/Doc/FFCatalog/fig/ff2/sim_demo_4quadrants.py
+++ b/Doc/FFCatalog/fig/ff2/sim_demo_4quadrants.py
@@ -2,7 +2,7 @@
 Plot form factor.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(200, -5, 5, -5, 5)
@@ -12,7 +12,7 @@ results = []
 for i in range(n):
     theta = pars[i]
     title = r'$\vartheta=%d^\circ$' % theta
-    ff = ba.FormFactorTruncatedSphere(4.2*nanometer, 6.1*nanometer, 0)
+    ff = ba.FormFactorTruncatedSphere(4.2*nm, 6.1*nm, 0)
     trafo = ba.RotationY(theta*degree)
     data = bp.run_simulation(det, ff, trafo)
     results.append(bp.Result(i, data, title))
diff --git a/Doc/FFCatalog/fig/ff2/sim_det_box.py b/Doc/FFCatalog/fig/ff2/sim_det_box.py
index 69698aa9605187020d00405d2aef65edcf4a46e5..06901d5f9ff39faa9dd975c8e60b54bf8a4166a4 100644
--- a/Doc/FFCatalog/fig/ff2/sim_det_box.py
+++ b/Doc/FFCatalog/fig/ff2/sim_det_box.py
@@ -2,7 +2,7 @@
 Plot form factors.
 """
 import bornagain as ba
-from bornagain import nanometer, degree
+from bornagain import nm, degree
 import bornplot as bp
 
 det = bp.Detector(1000, 0, 5, 0, 5)
diff --git a/Examples/Demos/FitCylindersPrisms_movie.py b/Examples/Demos/FitCylindersPrisms_movie.py
index 8b39f86c8f566bf52844a85cd297770246b01e11..87431c3cd72ccaac876cefff4c0711db21a69b11 100644
--- a/Examples/Demos/FitCylindersPrisms_movie.py
+++ b/Examples/Demos/FitCylindersPrisms_movie.py
@@ -34,10 +34,10 @@ fig = plt.figure(1)
 max_line_length = 30
 
 
-def get_sample(cylinder_height=1.0*nanometer,
-               cylinder_radius=1.0*nanometer,
-               prism_length=2.0*nanometer,
-               prism_height=1.0*nanometer):
+def get_sample(cylinder_height=1.0*nm,
+               cylinder_radius=1.0*nm,
+               prism_length=2.0*nm,
+               prism_height=1.0*nm):
     """
     Build the sample representing cylinders and pyramids on top of
     substrate without interference.
@@ -74,7 +74,7 @@ def create_real_data():
     This function has been used once to generate refdata_fitcylinderprisms.int
     """
     # creating sample with set of parameters we will later try to find during the fit
-    sample = get_sample(5.0*nanometer, 5.0*nanometer, 5.0*nanometer, 5.0*nanometer)
+    sample = get_sample(5.0*nm, 5.0*nm, 5.0*nm, 5.0*nm)
     simulation = get_simulation()
     simulation.setSample(sample)
     simulation.runSimulation()
@@ -200,13 +200,13 @@ def run_fitting():
     fit_suite.attachObserver(draw_observer)
 
     # setting fitting parameters with starting values
-    fit_suite.addFitParameter("*Cylinder/Height", 2.*nanometer,
+    fit_suite.addFitParameter("*Cylinder/Height", 2.*nm,
                               Limits.limited(0.01, 10.0))
-    fit_suite.addFitParameter("*Cylinder/Radius", 2.*nanometer,
+    fit_suite.addFitParameter("*Cylinder/Radius", 2.*nm,
                               Limits.limited(0.01, 10.0))
-    fit_suite.addFitParameter("*Prism3/Height", 2.*nanometer,
+    fit_suite.addFitParameter("*Prism3/Height", 2.*nm,
                               Limits.limited(0.01, 10.0))
-    fit_suite.addFitParameter("*Prism3/Length", 2.*nanometer,
+    fit_suite.addFitParameter("*Prism3/Length", 2.*nm,
                               Limits.limited(0.01, 10.0))
 
     # # Now we create first fig strategy which will run first minimization round using Genetic minimizer.
diff --git a/Examples/Demos/simul_demo_cyl_SSCA.py b/Examples/Demos/simul_demo_cyl_SSCA.py
index 1a4e435156245b736158f0038b17862378a0049b..f2df31acddf31794a9623dffa80ad42738a849d2 100644
--- a/Examples/Demos/simul_demo_cyl_SSCA.py
+++ b/Examples/Demos/simul_demo_cyl_SSCA.py
@@ -19,9 +19,9 @@ def RunSimulation():
     mLayer = HomogeneousMaterial("Layer", 2e-5, 2e-8)
 
     # collection of particles
-    cylinder_ff1 = FormFactorCylinder(2*nanometer, 5*nanometer)
-    cylinder_ff2 = FormFactorCylinder(3*nanometer, 6*nanometer)
-    cylinder_ff3 = FormFactorCylinder(4*nanometer, 7*nanometer)
+    cylinder_ff1 = FormFactorCylinder(2*nm, 5*nm)
+    cylinder_ff2 = FormFactorCylinder(3*nm, 6*nm)
+    cylinder_ff3 = FormFactorCylinder(4*nm, 7*nm)
     cylinder1 = Particle(mParticle, cylinder_ff1)
     cylinder2 = Particle(mParticle, cylinder_ff2)
     cylinder3 = Particle(mParticle, cylinder_ff3)
@@ -29,8 +29,8 @@ def RunSimulation():
     particle_layout.addParticle(cylinder1)
     particle_layout.addParticle(cylinder2)
     particle_layout.addParticle(cylinder3)
-    interference = InterferenceFunctionRadialParaCrystal(5*nanometer)
-    pdf = FTDistribution1DGauss(1*nanometer)
+    interference = InterferenceFunctionRadialParaCrystal(5*nm)
+    pdf = FTDistribution1DGauss(1*nm)
     interference.setProbabilityDistribution(pdf)
     # set coupling between size and space
     interference.setKappa(2)
@@ -42,7 +42,7 @@ def RunSimulation():
     substrate_layer = Layer(mSubstrate)
     multi_layer = MultiLayer()
     multi_layer.addLayer(vacuum_layer)
-    roughness = LayerRoughness(10*nanometer, 3, 20*nanometer)
+    roughness = LayerRoughness(10*nm, 3, 20*nm)
     multi_layer.addLayerWithTopRoughness(substrate_layer, roughness)
 
     # build and run experiment
diff --git a/Examples/Demos/simul_demo_cylsphere.py b/Examples/Demos/simul_demo_cylsphere.py
index 1179d4e3f351c164526a555da675e4816c1204da..79d2bd7c539d51cdcdbcd685dde66e26375feda2 100644
--- a/Examples/Demos/simul_demo_cylsphere.py
+++ b/Examples/Demos/simul_demo_cylsphere.py
@@ -18,15 +18,15 @@ def RunSimulation():
     mParticle = HomogeneousMaterial("Particle", 6e-4, 2e-8)
 
     # collection of particles
-    cylinder_ff = FormFactorCylinder(2*nanometer, 5*nanometer)
+    cylinder_ff = FormFactorCylinder(2*nm, 5*nm)
     cylinder = Particle(mParticle, cylinder_ff)
-    sphere_ff = FormFactorFullSphere(4*nanometer)
+    sphere_ff = FormFactorFullSphere(4*nm)
     sphere = Particle(mParticle, sphere_ff)
     particle_layout = ParticleLayout()
     particle_layout.addParticle(cylinder)
     particle_layout.addParticle(sphere)
-    interference = InterferenceFunctionRadialParaCrystal(20*nanometer)
-    pdf = FTDistribution1DGauss(2*nanometer)
+    interference = InterferenceFunctionRadialParaCrystal(20*nm)
+    pdf = FTDistribution1DGauss(2*nm)
     interference.setProbabilityDistribution(pdf)
     particle_layout.setInterferenceFunction(interference)
 
diff --git a/Examples/Demos/simul_demo_lattice1.py b/Examples/Demos/simul_demo_lattice1.py
index e35b40aa9516f2c2d8cb80bcc8a133dbeadda8d6..dae5926a1ae8d9935f8c718bdef0134235393c10 100644
--- a/Examples/Demos/simul_demo_lattice1.py
+++ b/Examples/Demos/simul_demo_lattice1.py
@@ -20,7 +20,7 @@ def RunSimulation():
     mParticle = HomogeneousMaterial("Particle", 6e-4, 2e-8)
 
     # particle
-    cylinder_ff = FormFactorCylinder(5*nanometer, 5*nanometer)
+    cylinder_ff = FormFactorCylinder(5*nm, 5*nm)
     cylinder = Particle(mParticle, cylinder_ff.clone())
     position = kvector_t(0.0, 0.0, 0.0)
     cylinder.setPosition(position)
@@ -28,8 +28,8 @@ def RunSimulation():
     particle_layout.addParticle(cylinder, 1.0)
 
     # interference function
-    interference = InterferenceFunction2DLattice(ba.SquareLattice2D(10.0*nanometer))
-    pdf = FTDecayFunction2DCauchy(300.0*nanometer/2.0/M_PI, 100.0*nanometer/2.0/M_PI,
+    interference = InterferenceFunction2DLattice(ba.SquareLattice2D(10.0*nm))
+    pdf = FTDecayFunction2DCauchy(300.0*nm/2.0/M_PI, 100.0*nm/2.0/M_PI,
                                   0)
     interference.setDecayFunction(pdf)
     particle_layout.setInterferenceFunction(interference)
diff --git a/Examples/Demos/simul_demo_lattice2.py b/Examples/Demos/simul_demo_lattice2.py
index abbb6d155429d6176174c06fb1197be670890872..1d911220f27b42292ff3bf1f200688e2e2fc4800 100644
--- a/Examples/Demos/simul_demo_lattice2.py
+++ b/Examples/Demos/simul_demo_lattice2.py
@@ -20,21 +20,21 @@ def RunSimulation():
     mParticle = HomogeneousMaterial("Particle", 6e-4, 2e-8)
 
     # particle 1
-    cylinder_ff = FormFactorCylinder(5*nanometer, 5*nanometer)
+    cylinder_ff = FormFactorCylinder(5*nm, 5*nm)
     cylinder = Particle(mParticle, cylinder_ff)
     position = kvector_t(0.0, 0.0, 0.0)
     cylinder.setPosition(position)
     particle_layout1 = ParticleLayout()
     particle_layout1.addParticle(cylinder, 1.0)
     # particle 2
-    position_2 = kvector_t(5.0*nanometer, 5.0*nanometer, 0.0)
+    position_2 = kvector_t(5.0*nm, 5.0*nm, 0.0)
     cylinder.setPosition(position_2)
     particle_layout2 = ParticleLayout()
     particle_layout2.addParticle(cylinder, 1.0)
 
     # interference function
-    interference = InterferenceFunction2DLattice(ba.SquareLattice2D(10.0*nanometer))
-    pdf = FTDecayFunction2DCauchy(300.0*nanometer/2.0/M_PI, 100.0*nanometer/2.0/M_PI,
+    interference = InterferenceFunction2DLattice(ba.SquareLattice2D(10.0*nm))
+    pdf = FTDecayFunction2DCauchy(300.0*nm/2.0/M_PI, 100.0*nm/2.0/M_PI,
                                   0)
     interference.setDecayFunction(pdf)
     particle_layout1.setInterferenceFunction(interference)
diff --git a/Examples/Demos/simul_demo_movie.py b/Examples/Demos/simul_demo_movie.py
index 93b39d5e25cfc724d932e65b1f3981c692a42354..ba65971aeab866b871e764b453b6c7fbf2808a04 100644
--- a/Examples/Demos/simul_demo_movie.py
+++ b/Examples/Demos/simul_demo_movie.py
@@ -32,7 +32,7 @@ def RunSimulation():
 
     # interference function
     interference = InterferenceFunctionRadialParaCrystal(distance)
-    pdf = FTDistribution1DGauss(3*nanometer)
+    pdf = FTDistribution1DGauss(3*nm)
     interference.setProbabilityDistribution(pdf)
     particle_layout.setInterferenceFunction(interference)
 
@@ -59,9 +59,9 @@ def SetParameters(i):
     global radius
     global height
     global distance
-    radius = (1. + (3.0/Nframes)*i)*nanometer
-    height = (1. + (4.0/Nframes)*i)*nanometer
-    distance = (10. - (1.0/Nframes)*i)*nanometer
+    radius = (1. + (3.0/Nframes)*i)*nm
+    height = (1. + (4.0/Nframes)*i)*nm
+    distance = (10. - (1.0/Nframes)*i)*nm
 
 
 #-------------------------------------------------------------
diff --git a/Examples/Demos/simul_demo_movie2.py b/Examples/Demos/simul_demo_movie2.py
index 4fa0116f83223f11307bb2922b880ef29db2f167..c1cf7499057fc4b9019a5f85d96033184ac845e4 100644
--- a/Examples/Demos/simul_demo_movie2.py
+++ b/Examples/Demos/simul_demo_movie2.py
@@ -30,8 +30,8 @@ def RunSimulation():
     particle_layout.addParticle(semisphere)
 
     # interference function
-    interference = InterferenceFunctionRadialParaCrystal(6*nanometer)
-    pdf = FTDistribution1DGauss(1*nanometer)
+    interference = InterferenceFunctionRadialParaCrystal(6*nm)
+    pdf = FTDistribution1DGauss(1*nm)
     interference.setProbabilityDistribution(pdf)
     particle_layout.setInterferenceFunction(interference)
 
@@ -60,12 +60,12 @@ def SetParameters(i):
     global radius
     global layer_thickness
     if i < Ngrowframes:
-        radius = (1. + (3.0/Ngrowframes)*i)*nanometer
-        layer_thickness = 0.01*nanometer
+        radius = (1. + (3.0/Ngrowframes)*i)*nm
+        layer_thickness = 0.01*nm
     else:
-        radius = 4.*nanometer
+        radius = 4.*nm
         layer_thickness = (0.01 + (0.5/(Nframes - Ngrowframes))*
-                           (i - Ngrowframes))*nanometer
+                           (i - Ngrowframes))*nm
 
 
 #-------------------------------------------------------------
diff --git a/Examples/Demos/simul_demo_movie3.py b/Examples/Demos/simul_demo_movie3.py
index 9424048b1915955f21d4531f625922f679136739..3853450ef166610d34b2ebd698fac225e13874fe 100644
--- a/Examples/Demos/simul_demo_movie3.py
+++ b/Examples/Demos/simul_demo_movie3.py
@@ -24,9 +24,9 @@ def RunSimulation():
     mLayer = HomogeneousMaterial("Layer", 2e-5, 2e-8)
 
     # collection of particles
-    cylinder_ff1 = FormFactorCylinder(2*nanometer, 5*nanometer)
-    cylinder_ff2 = FormFactorCylinder(3*nanometer, 6*nanometer)
-    cylinder_ff3 = FormFactorCylinder(4*nanometer, 7*nanometer)
+    cylinder_ff1 = FormFactorCylinder(2*nm, 5*nm)
+    cylinder_ff2 = FormFactorCylinder(3*nm, 6*nm)
+    cylinder_ff3 = FormFactorCylinder(4*nm, 7*nm)
     cylinder1 = Particle(mParticle, cylinder_ff1)
     cylinder2 = Particle(mParticle, cylinder_ff2)
     cylinder3 = Particle(mParticle, cylinder_ff3)
@@ -34,8 +34,8 @@ def RunSimulation():
     particle_layout.addParticle(cylinder1)
     particle_layout.addParticle(cylinder2)
     particle_layout.addParticle(cylinder3)
-    interference = InterferenceFunctionRadialParaCrystal(6*nanometer)
-    pdf = FTDistribution1DGauss(.5*nanometer)
+    interference = InterferenceFunctionRadialParaCrystal(6*nm)
+    pdf = FTDistribution1DGauss(.5*nm)
     interference.setProbabilityDistribution(pdf)
     # set coupling between size and space
     interference.setKappa(kappa)
@@ -47,7 +47,7 @@ def RunSimulation():
     substrate_layer = Layer(mSubstrate)
     multi_layer = MultiLayer()
     multi_layer.addLayer(vacuum_layer)
-    roughness = LayerRoughness(10*nanometer, 3, 20*nanometer)
+    roughness = LayerRoughness(10*nm, 3, 20*nm)
     multi_layer.addLayerWithTopRoughness(substrate_layer, roughness)
 
     # build and run experiment
diff --git a/Tests/Functional/Python/PyCore/polmagcylinders1.py b/Tests/Functional/Python/PyCore/polmagcylinders1.py
index 0591a7a2ca3bb04b28d4a9bb95ed9a8e1b3c50d4..373d79bfd083cd0f798915be175f0dfd8ca78259 100644
--- a/Tests/Functional/Python/PyCore/polmagcylinders1.py
+++ b/Tests/Functional/Python/PyCore/polmagcylinders1.py
@@ -3,7 +3,7 @@
 from __future__ import print_function
 import gzip, numpy, os, sys, utils
 import bornagain as ba
-from bornagain import nanometer, angstrom, degree
+from bornagain import nm, angstrom, degree
 
 
 # ----------------------------------
@@ -18,7 +18,7 @@ def runSimulation():
 
     magParticle = ba.HomogeneousMaterial("magParticle", 6e-4, 2e-8, magnetic_field)
     # collection of particles
-    cylinder_ff = ba.FormFactorCylinder(5*nanometer, 5*nanometer)
+    cylinder_ff = ba.FormFactorCylinder(5*nm, 5*nm)
     cylinder = ba.Particle(magParticle, cylinder_ff)
 
     particle_layout = ba.ParticleLayout()
diff --git a/Tests/Functional/Python/PyCore/polmagcylinders2.py b/Tests/Functional/Python/PyCore/polmagcylinders2.py
index 71c8522d420e0b13ae4c0b9c0a02a29db68e345d..76094f2516b2aa35ec35619114a6d71633a37fd3 100644
--- a/Tests/Functional/Python/PyCore/polmagcylinders2.py
+++ b/Tests/Functional/Python/PyCore/polmagcylinders2.py
@@ -24,7 +24,7 @@ def getSimulationIntensity(rho_beam, efficiency):
 
     magParticle = HomogeneousMaterial("magParticle", 5e-6, 0.0, magnetization)
     # collection of particles
-    cylinder_ff = FormFactorCylinder(5*nanometer, 5*nanometer)
+    cylinder_ff = FormFactorCylinder(5*nm, 5*nm)
     cylinder = Particle(magParticle, cylinder_ff)
 
     particle_layout = ParticleLayout()
diff --git a/Tests/Performance/Python/test_performance.py b/Tests/Performance/Python/test_performance.py
index 0756cb5e23079836b4dd6ec2b7a293577d049a38..ed50a45c496a25bf9ae4c1fa009f9bc1ba8c0cc9 100755
--- a/Tests/Performance/Python/test_performance.py
+++ b/Tests/Performance/Python/test_performance.py
@@ -163,7 +163,7 @@ class CustomTest(FactoryTest):
         m_particle = HomogeneousMaterial("Particle", 6e-4, 2e-8)
 
         # collection of particles
-        ff = CustomFormFactor(343.0*nanometer, 7.0*nanometer)
+        ff = CustomFormFactor(343.0*nm, 7.0*nm)
         particle = Particle(m_particle, ff)
         particle_layout = ParticleLayout()
         particle_layout.addParticle(particle, 1.0)