ChemInform Abstract: Hydrothermal Synthesis and Characterization of Novel One‐Dimensional Tellurites of Molybdenum(VI), A₄Mo₆TeO₂₂×2H₂O (A: NH₄, Rb).

Abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis and Characterization of Ammonium Potassium Tellurium Polyoxomolybdate: (NH4)2K2TeMo6O22·2H2O with One-Dimensional Anionic Polymeric Chain [TeMo6O22]4−

“…It should be mentioned that the minor weight gains along with the flat exothermic band that occurred in the range of RT (room temperature)-200 • C may be caused by the N 2 absorption of the material. Two main endothermic peaks are observed at 290 and 330 • C, both lower than the corresponding decomposition temperatures of 310 and 378 • C of single ammonium phase (NH 4 ) 4 Mo 6 TeO 22 •2H 2 O [34]. The total weight loss ratio was consistent with the theoretical one (total water and ammonium) of ~6.0%.…”

“…The strong and The infrared absorption spectra from 4000 to 400 cm −1 range are shown in Figure 4. The several peaks in the band range of 3201−2767 cm −1 can be ascribed to the symmetric stretching vibrations of the tetrahedral ammonium ion, and the two sharp peaks at 1437 and 1396 cm −1 are related to the asymmetric stretching modes [18,22,34]. The strong and broad absorption around 3440 cm −1 is due to the stretching modes of water molecules, and the peaks at 1590 and 1637 cm −1 are caused by the H-O-H bending modes of crystalline water [55,56].…”

“…The bands at 756 and 644 cm −1 can be attributed to the Te-O vibrations. The peaks at 555, 488, 463, and 432 cm −1 may be ascribed to the Te-O-Te, Te-O-Mo, or Mo-O-Mo bending vibrations [34,43].…”

“…Recently, rare earth elements have been introduced into the hexamolybdotellurate clusters as structural linkers to form one-dimensional chain-like architecture [31][32][33]. Another example in the A-Te-Mo-O system is the novel tellurium polymolybdate A 4 TeMo 6 O 22 •2H 2 O (A = NH 4 , Rb), which crystallize in the one-dimensional [TeMo 6 O 24 ] 6− anionic chains with NH 4 + /Rb + cations held together [34]. Encouraged by the surprising compositional variability and structural diversity of the tellurium molybdate system, we attempted to explore new compounds in the K-Te-Mooxide system.…”

Understanding of the structural chemistry in the uranium oxo-tellurium system under HT/HP conditions

“…Tellurium is typically present as Te IV or Te VI and hereby in form of oxo-anions, tellurites and tellurates, respectively. Te IV is known to adopt several coordination environments, for example, pyramidal TeO 3 , disphenoidal TeO 4 and square pyramidal TeO 5 (Balraj and Vidyasagar, 1999;Kim et al, 2007a;Kim et al, 2010). A further inter-connection via corner-sharing can lead to complex oxotellurium polymers (Lindqvist and Moret, 1973;Hafidi et al, 1986;Mao et al, 2008;Lin et al, 2013).…”