The framework of K(Co-II,Al)(2)(PO4)(2) consists of corner-sharing (Co
/Al)O-4 and PO4 tetrahedra, which form large intersecting tunnels runn
ing along the three crystallographic axes, with the K atoms situated i
n the tunnels. Co-II and Al atoms are distributed over two tetrahedral
sites with almost equal probability The average Co(1)/Al(1)-O distanc
e of 1.826 (19) Angstrom and average Co(2)/Al(2)-O distance of 1.829 (
13) Angstrom reflect mixing of Co and Al at the metal-atom sites.