Synthesis and Characterization of the Thiogermanic Acids H₄Ge₄S₁₀ and H₂Ge₄S₉

Abstract

The synthesis and structure of the thiogermanic acids H4Ge4S10 and H2Ge4S9 are reported. A novel preparation method consisting of reacting germanium oxide with liquid hydrogen sulfide containing a trace amount of water is used to form Ge4S104-ions. Evaporating the hydrogen sulfide solution at room temperature leaves an unstable H4Ge4S10·xH2O product. The stoichiometry and structure of the thermally stable anhydrous phase are dependent on reaction time. An H4Ge4S10 product with an adamantane-like cage structure is obtained at shorter reaction times. Longer reaction times produce an H2Ge4S9 product with a more complex cage unit, a higher symmetry unit cell, and increased thermal stability. Raman, infrared, powder X-ray diffraction, and thermogravimetric data are reported for both structures.

Synthesis and characterization of potassium, rubidium, and cesium thiogermanate glasses

“…S-H stretching was not observed in the vibrational spectra. This is consistent with the thermal decomposition behavior of the thiogermanic acid phases [8]. Additionally, no evidence for excess sulfur resulting from the decomposition of the hydrosulfides into higher polysulfides was observed in the vibrational spectra.…”

Synthesis and characterization of germanium sulfide aerogels

“…The peaks at 346 and 348 cm À1 are assigned to the Ge-S-Ge A 1 symmetric stretch mode, while that at 374 cm À1 is assigned to the so-called A c 1 companion stretch mode [31][32][33][34]. The band at 415 cm À1 is attributed to GeS À , arising from a possible cleavage of Ge-S-Ge bridges [35,36], while those at 437-440 cm À1 are assigned to the stretching mode of S-S dimers at the surface [32,34]. For the crystalline aerogels, all of these bands are also seen, but there are additional bands at 520, 774 and 881 cm À1 (Fig.…”

Preparation and characterization of new proton conducting chalcogenide glasses

“…The H-S stretch in the thioboric acid and thiogermanic acid is observed at $2532 cm À1 and $2519 cm À1 , respectively. H-S modes in these two binary systems are quite similar [10] and hence, in a ternary thioborogermanate system, it is difficult to determine whether the protons are preferentially bonded to borate or germanate units. More studies such as the 1 H-NMR and far-IR study of germanate structures are necessary to determine the nature of the proton bonding.…”