Two New Tetramethylammonium Zinc Phosphates: N(CH3)4·Zn(HPO4)(H2PO4), an Open Framework Phase Built up from a Low-Density 12-Ring Topology, and N(CH3)4·Zn(H2PO4)3, a Molecular Cluster

Abstract

The solution-phase syntheses and X-ray single crystal structures of N(CH3)4·Zn(HPO4)(H2PO4) and N(CH3)4·Zn(H2PO4)3, two new tetramethylammonium (TMA) zinc phosphates, are described. N(CH3)4·Zn(HPO4)(H2PO4) is a three-dimensional framework phase built up from ZnO4, HPO4, and H2PO4tetrahedra sharing vertices. The polyhedral connectivity results in a novel, low-density framework topology, based on tetrahedral 12-rings. TMA cations provide extra-framework charge balancing, and occupy the 12-ring channel network. N(CH3)4·Zn(H2PO4)3is a “zero-dimensional” (molecular) phase built up from the same polyhedral units, formed into discrete anionic clusters. Crystal data: N(CH3)4·Zn(HPO4)(H2PO4),Mr=332.49, monoclinic, space groupPc(No. 7),a=8.443 (2) Å,b=13.779 (4) Å,c=10.170 (2) Å,β=91.91 (2)°,V=1182.9 (5) Å3,Z=4,R(F)=4.69%,Rw(F)=5.46% [3284 observed reflections withI>3σ(I)]. N(CH3)4·Zn(HPO4)(H2PO4)3,Mr=430.49, triclinic, space groupP1(No. 2),a=8.950 (2) Å,b=10.068 (2) Å,c=10.263 (2) Å,α=61.649 (9)°,β=76.04 (2)°,γ=76.72 (1)°,V=782.5 (2) A3,Z=2,R(F)=4.22%Rw(F)=4.77% [3038 observed reflections withI>3σ(I)].