About the tolerance factor for pyrochlores and related structures
  In this work a new empirical tolerance factor for compounds with pyrochlore structure is proposed. This suggested tolerance factor is based on experimental structural data and on the tolerance factors currently proposed. However, since it does not depend on the structural data, this new tolerance factor permits the prediction of some properties of these compounds directly. Also, a good structure stability field for the pyrochlore formation is observed when this tolerance factor is used. 
Rodolpho Mouta Monte Prado, Rosivaldo Xavier Silva and Carlos William   de Araujo Paschoal
cond-mat.mtrl-sci