The PNR to Relaxor Transition in PSN with nearest neighbor Pb-O divacancies

In previous work, molecular dynamics simulations based on a first-principles-derived effective Hamiltonian for ${\text{Pb}}_{1-\text{X}}\left({\text{Sc}}_{1/2}{\text{Nb}}_{1/2}\right){\text{O}}_{3-\text{X}}$ (PSN), with nearest-neighbor Pb-O divacancy pairs, was used to calculate ${\text{X}}_{[\text{Pb}-\text{O}]}$ vs. T, phase diagrams for PSN with: ideal rock-salt type chemical order; nanoscale chemical short-range order; and random chemical disorder. Here, we show that the phase diagrams should include additional regions in which a glassy relaxor-phase (or state) is predicted. With respect to phase diagram topology, these results strongly support the analogy between relaxors and magnetic spin-glass-systems.