Space Group Determination of Ba6-3xNd8+2xTi18O54
The space group of the solid solution phase Ba6-3x-RE8+2xTi18O54(RE = rare-earth cation) has been variously reported as Pba2 (No. 32), Pbn21(No. 33), Pbam (No. 55), or Pbnm (No. 62). New results are presented here which indicate that its correct space group assignment may be Pb21m (No. 26).
Rick Ubic, Ian M. Reaney, and William E. Lee. "Space Group Determination of Ba6-3xNd8+2xTi18O54" Journal of the American Ceramic Society 82.5 (1999): 1336-1338.