Structural study on NaXHfNCl system

NaxHfNCl powder samples with average sodium content x(av) = 0, 0.18, 0.29, and 0.80 have been studied. The neutron powder diffraction patterns exhibit the phase separation in NaxHfNCl system except for x = 0 and 0.29. Obtained phases are a pristine phase beta-HNCl, a superconducting phase NaxHfNCl (T-c = 22-19 K) with narrow x-width (x = 0.28-0.29), a non-superconducting crystalline phase Na0.9HfNCl, and a possible amorphous phase NaHfNCl (C) 2003 Elsevier B.V. All rights reserved.