diff --git a/src/phase_mechanical.f90 b/src/phase_mechanical.f90
index bddd4775e..88b86a8d9 100644
--- a/src/phase_mechanical.f90
+++ b/src/phase_mechanical.f90
@@ -264,8 +264,6 @@ module subroutine mechanical_init(phases)
       en = material_phaseEntry(co,ce)
       phase_mechanical_F(ph)%data(1:3,1:3,en)  = math_I3
       phase_mechanical_Fp(ph)%data(1:3,1:3,en) = material_O_0(ma)%data(co)%asMatrix()              ! Fp reflects initial orientation (see 10.1016/j.actamat.2006.01.005)
-      phase_mechanical_Fp(ph)%data(1:3,1:3,en) = phase_mechanical_Fp(ph)%data(1:3,1:3,en) &
-                                               / math_det33(phase_mechanical_Fp(ph)%data(1:3,1:3,en))**(1.0_pReal/3.0_pReal)
       phase_mechanical_Fe(ph)%data(1:3,1:3,en) = matmul(material_V_e_0(ma)%data(1:3,1:3,co), &
                                                         transpose(phase_mechanical_Fp(ph)%data(1:3,1:3,en)))
       phase_mechanical_Fi(ph)%data(1:3,1:3,en) = material_O_0(ma)%data(co)%rotate(math_inv33(material_V_e_0(ma)%data(1:3,1:3,co)))
diff --git a/src/rotations.f90 b/src/rotations.f90
index 6257fe7e4..5367f2c07 100644
--- a/src/rotations.f90
+++ b/src/rotations.f90
@@ -449,6 +449,7 @@ pure function qu2om(qu) result(om)
   om(1,3) = 2.0_pReal*(qu(2)*qu(4)+qu(1)*qu(3))
 
   if (sign(1.0_pReal,P) < 0.0_pReal) om = transpose(om)
+  om = om/math_det33(om)**(1.0_pReal/3.0_pReal)
 
 end function qu2om
 
@@ -602,6 +603,7 @@ pure function om2qu(om) result(qu)
   endif
   if(sign(1.0_pReal,qu(1))<0.0_pReal) qu =-1.0_pReal * qu
   qu(2:4) = merge(qu(2:4),qu(2:4)*P,dEq0(qu(2:4)))
+  qu = qu/norm2(qu)
 
 end function om2qu