Structure of the aluminate ion in solutions at high pH

Microstructural Properties of High Level Waste Concentrates and Gels with raman and Infrared Spectroscopies

“…In contrast, the 620 cm-' band represents < 50% of the total Raman intensity when the Al concentration is 5 M (Figure 5b). These results are in agreement with Raman and IR studies of sodium aluminate solutions (17,20,21 ).…”

“…Moolenaar and coworkers (21) were among the first to assign the 537 and 692 cm-l bands to a dimeric hydroxide ion [(OH)3A10Al(OH)J2-species (21): 2 Al(OH)4 +-+ (OH)3-Al-O-Al-(OH)32-+ H20.…”

UV Raman spectroscopic study on the synthesis mechanism of zeolite X

“…2 gives the UV Raman spectra of the liquid phase in the zeolite X synthesis after 0, 1.0, 2.0, 2.5, 3.0, 3.5 and 4.0 h. Bands at 519, 620 and 1070 cm À1 are observed in the Raman spectra of the initial gel. The band at 620 cm À1 is assigned to the Al±O symmetric stretching mode of Al OH À 4 species in the solution [15,16,19,30,31]. The band at 519 cm À1 is attributed to amorphous silicate [16].…”

The structure of hyperalkaline aqueous solutions containing high concentrations of gallium – a solution X-ray diffraction and computational study

“…The main results of the aluminate structural analysis are: (i) The monomeric aluminate form with tetrahedral structure is confirmed. 8 (ii) Beyond that, a more extended structure with two tetrahedron (that is: dimeric aluminate species) is possible, both from experimental 8,[42][43][44][45] and from computational 46 means further structural units are also possible, even if they were not fully confirmed. Moreover, spectroscopic and other studies reported the extended network of numerous structural forms in aluminate solutions, however, they are scarcely confirmed.…”