Template Effect of Chain-Type Polyamines on Pore Augmentation: Five Open-Framework Zinc Phosphates with 16-Ring Channels

Five new zinc phosphates with differently unique 3D framework topologies, (H<sub>3</sub>dien)[Zn<sub>3</sub>(HPO<sub>4</sub>)<sub>3</sub>(PO<sub>4</sub>)] (<b>1</b>), (H<sub>2</sub>dien)<sub>1.5</sub>[Zn<sub>3</sub>(HPO<sub>4</sub>)<sub>3</sub>(PO<sub>4</sub>)] (<b>2</b>), (H<sub>3</sub>dien)[Zn<sub>3</sub>(H<sub>2</sub>PO<sub>4</sub>)(HPO<sub>4</sub>)(PO<sub>4</sub>)<sub>2</sub>] (<b>3</b>), (H<sub>3</sub>dien)[Zn<sub>3</sub>(HPO<sub>4</sub>)<sub>3</sub>(PO<sub>4</sub>)]·1.5H<sub>2</sub>O (<b>4</b>), and (H<sub>4</sub>tepa)<sub>0.5</sub>[Zn<sub>2.5</sub>(HPO<sub>4</sub>)<sub>2</sub>(PO<sub>4</sub>)]·1.5H<sub>2</sub>O (<b>5</b>), where dien = H<sub>2</sub>NC<sub>2</sub>H<sub>4</sub>NHC<sub>2</sub>H<sub>4</sub>NH<sub>2</sub> and tepa = H<sub>2</sub>N(C<sub>2</sub>H<sub>4</sub>NH)<sub>3</sub>C<sub>2</sub>H<sub>4</sub>NH<sub>2</sub>, have been synthesized under mild hydrothermal or solvothermal conditions and characterized by single-crystal X-ray diffraction, thermal analysis, solid-state NMR, UV–vis, or photoluminescence spectroscopy. Both the 7-atom-skeleton-long dien and the 13-atom-skeleton-long tepa have created 16-membered ring (16R) channels as a common feature in structures <b>1</b>–<b>5</b>. Their inorganic frameworks are built up with tetrahedra of ZnO<sub>4</sub>, PO<sub>4</sub>, and HPO<sub>4</sub> (plus H<sub>2</sub>PO<sub>4</sub> in <b>3</b>) and may all be described as constructed from two-dimensional nets and one- or zero-dimensional units as linkers. Compounds <b>1</b>–<b>4</b> have the same Zn/P ratio but possess varied amount of nonframework volume. They are the first examples with dien as template in extra-large-channel structures of zincophosphates. In comparison, the framework of <b>5</b> contains a higher value in Zn/P and larger nonframework volume than that in the 24R-channel structure of ND-1. The 16R channels in <b>1</b> and <b>2</b> are one-dimensional while those in <b>3</b>, <b>4</b>, and <b>5</b> are unprecedentedly two-dimensional. In this paper, the synthesis, thermal property, NMR, reflectance UV–vis absorption, and photoluminescence study of <b>1</b>–<b>5</b> are described; framework topologies, structure relationship, the charge and location of templates, and channel characteristic vs nonframework volume are discussed.