Isosteric molecules in non-isomorphous structures: A new route to new structures. The example of 9,10-dihaloanthracene

When isosteric molecules with non-isomorphous structures are combined into solid solutions they may arrange in yet another way: despite their obvious similarity at molecular level, 9,10-dichloro- and dibromoanthracene differ clearly in their crystal structures. From these two components a solid solution with the latter compound as the minor constituent can be obtained as a phase pure product—it represents an entirely new structure type.