title: Cs1-xSn1-xBi9+Se15 and Cs1.5-3xBi9.5+xSe15: members of the homologous superseries Am[M1+lSe2+l]2m[M1 + 2l+nSe3 + 3l+n] (A = alkali metal, M = Sn and Bi) allowing structural evolution in three different dimensions.
abstract: Cs1-xSn1-xBi9+xSe15 and Cs1.5-3xBi9.5+xSe15 crystallize in a new structure type which does not belong to but is closely related to the members of the homologous series Am[M6-Se8]m[M5+nSe9+n]; the new phases reveal a third dimension of structural evolution for this series according to the formula Am[M1+lSe2+l]2m[M1 + 2l + nSe3 + 3l+n].
authors.affiliation: Department of Chemistry and Center for Fundamental Materials Research, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: A
authors.initials: A
authors.lastname: Mrotzek
authors.forename: L
authors.initials: L
authors.lastname: Iordanidis
authors.forename: M G
authors.initials: MG
authors.lastname: Kanatzidis