Reports that in PbZn⅓Nb⅔O3–x%PbTiO3 (PZN–PT) relaxor ferroelectric crystals an 'X-phase' exists, which has a cubic interior and a 10–50 μm thick rhombohedrally distorted surface, have been re-examined to resolve the effect of electric poling. The crystal structure of electrically poled and de-poled PZN–4.5%PT single crystals has been studied using a novel rotating single-crystal method on the high-resolution neutron powder diffractometer at the ISIS Facility. The recorded patterns are neutron time-of-flight analogues to the zero layer lines of rotating single-crystal x-ray diffraction patterns. Both  and  zones were examined and they demonstrate unequivocally that the crystals do not have a cubic core. There appears now to be direct evidence against the occurrence of the 'X-phase' in every circumstance in which, based on synchrotron studies, it was previously proposed to exist.
Journal of Physics - Condensed Matter Vol. 19, Issue 23