| Popis: |
A few new pure beryllophosphate molecular sieves have been hydrothermally synthesized by using concentrated amines such as triethylene tetramine, polyethylene polyamine, piperazine, and pyridine as structure-directing agents. The structures of these compounds were characterized by single-crystal X-ray diffraction. Their structures are similar to the zeolite gmelinite, gismondine, and ABW frameworks, named BePO4−GME, BePO4−GIS, and BePO4−ABW, respectively. BePO4−GME is the first instance of phosphate with GME topology. The organic template was found in the 12-membered ring channels running along [001]; the thermal analysis indicates that the inorganic framework collapses above 400 °C after the removal of the template. BePO4−GIS is a new beryllophosphate, which has three-dimensional, intersecting 8-membered ring channels along the crystallographic [001], [010], and [111] directions. In the concentrated amines system these resulting compounds have similar structural characterizations: Their frameworks that ... |
