Anisotropic compression of a synthetic potassium aluminogermanate zeolite with gismondine topology

Journal Article · Sun Aug 01 04:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2010.07.041· OSTI ID:991726

Jang, Y N; Kao, C; Vogt, T; Lee, Y

Compression behavior of a potassium aluminogermanate with a gismondine framework topology (K-AlGe-GIS) was studied using in-situ high-pressure synchrotron X-ray powder diffraction. In contrast to the potassium gallosilicate analogue (K-GaSi-GIS), no elastic anomaly due to pressure-induced hydration and/or cation relocation was observed in K-AlGe-GIS. The Birch-Murnaghan fit to the pressure-volume data results in a bulk modulus of B{sub 0} = 31(1) GPa. The derived linear-axial compressibilities (i.e., {beta}{sub a} = 0.0065(5) GPa{sup -1}, {beta}{sub b} = 0.0196(4) GPa{sup -1}, {beta}{sub c} = 0.0081(7) GPa{sup -1}) indicate that the b-axis, normal to the 8-ring channels, is about three times more compressible than the a and c axes, parallel to the elliptical 8-ring channels. As a consequence a gradual flattening of the so-called 'double crankshaft' structural building units of the gismondine framework is observed. In K-AlGe-GIS, this flattening occurs almost linear with pressure, whereas it is nonlinear in the GaSi-analogue due to structural changes of the water-cation assembly under hydrostatic pressures.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: DOE - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 991726
• Report Number(s): BNL--94181-2010-JA; KC0401030
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 183; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
58 GEOSCIENCES
CATIONS
COMPRESSION
DIFFRACTION
HYDRATION
HYDROSTATICS
POTASSIUM
SYNCHROTRONS
TOPOLOGY
ZEOLITES