Synthesis, characterization and structure solution of ULS-1 |ETMA8(H2O)20|[Si24O48(OH)8], a layered silicate composed of half-sodalite cages

• Hydrothermal synthesis with ETMA+ containing solutions yields ULS-1 at 100 °C.
• ULS-1 is a highly siliceous layered silicate composed of [4262] half sodalite cages.
• ETMA+ increases the interlayer spacing to ∼8.3 Å from the previously observed ∼8 Å.
• ULS-1 crystallizes in Ibam with a = 28.909 Å, b = 8.380 Å, c = 11.569 Å.

UOP layered silicate-1 (ULS-1), a highly siliceous layered silicate composed of [4262] half sodalite cages, has been synthesized hydrothermally at 100 °C from solutions containing ethyltrimethylammonium hydroxide and silica or aluminosilicate sources and the structure solved from powder XRD data in the Ibam spacegroup with a = 28.909 Å, b = 8.380 Å, c = 11.569 Å at room temperature. TGA/MS and NMR, Raman and IR spectroscopic characterization were utilized to examine the properties of ULS-1 and provide information for structure solution. ULS-1 contains the same silicate layer structure and stacking as that found in RUB-15 and DLM-2, but with ethyltrimethylammonium (ETMA) cations in place of tetramethylammonium stabilizing the half sodalite cages. The presence of ETMA increases the interlayer spacing to ∼8.3 Å from the previously observed 8 Å, but also slightly increases the c unit cell constant in the layer direction.

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