XANES Studies of Thallium Compounds and Valence States and Local Environment of Thallium in Some of its Superconducting Cuprates

Oxidative scavenging of thallium by birnessite: Explanation for thallium enrichment and stable isotope fractionation in marine ferromanganese precipitates

“…Linear combination fitting (LCF) of the data is summarized in Table 1. In agreement with published Tl L3-edge XANES spectra, our monovalent standard shows a single absorption peak while our trivalent standards show a weak peak, followed by a shoulder on rising absorption, culminating in a strong absorption peak (e.g., Scheckel et al, 2004;Agarwal and Vishnoi, 2005;Dutrizac et al, 2005). The overall profiles of our Tl-sorbed ferrihydrite (Tl_Fh_pH8_48 h), Tc-Na-birnessite (Tl_TcNaBir_pH8_48 h) and todorokite (Tl_Tod_pH8_2 h and Tl_Tod_pH8_336 h) samples are very similar to that of TlNO 3 (s) (Fig.…”

Thallium-rich rust scales in drinkable water distribution systems: A case study from northern Tuscany, Italy

“…8a and 8b. Results on standards agree with literature data (e.g., Scheckel et al, 2004;Agarwal and Vishnoi, 2005;Dutrizac et al, 2005;Peacock and Moon, 2012), as monovalent compounds show a single absorption peak while Tl2O3 shows a weak peak, followed by a shoulder on rising absorption, culminating in a marked peak. The XANES region of samples P#2, res_P#2, and P#3 spectra closely resemble that of Tl2O3 (absorption edge at ~12669 eV), despite, especially in the case of P#3 sample, the presence of a shoulder situated in correspondence of the position of Tl(I) edge, clearly observable in the normalized as well as in the first derivative absorption spectra.…”

XANES of the AuLIII edge in gold metal and in two compounds AuCN and AuCl3

“…On the basis of the valence and ionicity rule [19][20][21][22] one may expect nearly the same shift in the two compounds. Such discrepancies in the observed shifts of edges are well known [23][24][25][26][27]. Vishnoi [23] observed the shift in PbO, which is 52% ionic, is 3.2 eV, while in PbS which is only 13% ionic, that is largely covalent, it is 4.0 eV.…”