Vibrational polarizabilities of Na3 computed from density functional theory property surfaces and a variational vibrational calculation

We have calculated the polarizability of Na3 at 300 K. We compute a Na3 potential energy surface and also electronic dipole moment and electronic polarizability surfaces from density functional theory. Using these surfaces we compute exact field-dependent vibrational energy levels, wavefunctions and the polarizability. We find that for Na3 the effect of vibration and rotation is small. It does not explain the discrepancy between an experimental measurement (471 ± 16 bohr3) and an earlier calculation of the electronic polarizability 394 bohr3.