Dear Material Studio Community,
 

I would like to ask about deuterium simulations using DMol³ in Material Studio 7.0.
 

As I understand it, geometry optimization and single-point energy calculations in DFT cannot distinguish between hydrogen (H) and deuterium (D). Within the Born–Oppenheimer approximation, nuclei are treated as fixed point charges, and electronic energies depend only on nuclear charge and geometry. Since H and D have identical nuclear charges and electronic structures, their electronic energies should be the same.
 

However, I performed a geometry optimization followed by a frequency calculation for a gas-phase molecule, CpZr(NMe₂)₃. To model deuterium, I replaced all hydrogen atoms in the Cp ligand with D by manually changing the atomic mass from 1.008 u to 2.014 u (as shown in the attached image).
 

However, in the output file for the frequency calculation, the D atoms are still treated as hydrogen, with the mass reported as 1.008 u.
 

Does this indicate that my version of Material Studio does not support deuterium in DFT simulations, or am I missing a specific setting or procedure?
 

Thank you for your assistance.
Best regards