Abstract
Recent results, including high pressure data, on the low temperature properties of KTa1-xNbxO3 (KTN) are presented and discussed. Most of the emphasis is on the question of whether the low temperature polar phase in dilute KTN (x≈0.02) arises from the spontaneous displacement of ions below T c (i.e. a static structural phase transition) or from the freezing of impurity-induced dipolar motion. Much of the evidence argues against a bulk equilibrium phase transition and suggests the coexistence of random dipole freezing and slowly relaxing ordered clusters which grow with decreasing T. The likelihood of a pressure-induced crossover from normal ferroelectric ordering to dipolar glass behavior in soft T O mode systems is discussed and possible evidence for such a phenomenon is presented.

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