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Thallium chemistry is experiencing unprecedented importance. Therefore, it is valuable to characterize some of the simplest thallium compounds. Stationary points along the singlet and triplet Tl 2H 2 potential energy surface have been characterized. Stationary point geometries were optimized with the CCSD(T)/aug‐cc‐pwCVQZ‐PP method. Harmonic vibrational frequencies were computed at the same level of theory while anharmonic vibrational frequencies were computed at the CCSD(T)/aug‐cc‐pwCVTZ‐PP level of theory. Final energetics were obtained with the CCSDT(Q) method. Basis sets up to augmented quintuple‐zeta cardinality (aug‐cc‐pwCV5Z‐PP) were employed to obtain energetics in order to extrapolate to the complete basis set limits using the focal point approach. Zero‐point vibrational energy corrections were appended to the extrapolated energies in order to determine relative energies at 0 K. It was found that the planar dibridged isomer lies lowest in energy while the linear structure lies highest in energy. The results were compared to other group 13 M 2H 2 (M = B, Al, Ga, In, and Tl) theoretical studies and some interesting variations are found. With respect to experiment, incompatibilities exist. [ABSTRACT FROM AUTHOR]

We have investigated the NMR chemical shift of 205Tl in several thallium compounds, ranging from small covalent Tl(I) and Tl(III) molecules to supramolecular complexes with large organic ligands and some thallium halides. NMR calculations were run at the ZORA relativistic level, with and without spin‐orbit coupling using few selected GGA and hybrid functionals, namely BP86, PBE, B3LYP, and PBE0. We also tested solvent effects both at the optimization level and at the NMR calculation step. At the ZORA‐SO‐PBE0 (COSMO) level of theory we find a very good performance of the computational protocol that allows to discard or retain possible structures/conformations based on the agreement between the calculated chemical shift and the experimental value. [ABSTRACT FROM AUTHOR]

Thallium compounds, i.e. Tl+[S2P{OC6H3(2,5-(CH3)2)}2]− (1) and Tl+[S2P{OC6H3(3,5-(CH3)2)}2]− (2), stabilized by intra- and intermolecular triel bonds were isolated and characterized by FT-IR, NMR (31P, 1H and 13C) spectroscopy, and SC-XRD analysis. The crystal structures of 1 and 2 belong to monoclinic crystal systems with the space group C2/c and P21/n, respectively. Interestingly, the positively charged Tl atom is bonded attractively with the π-holes of the 1,1-dithioate moiety. These compounds exist in ionic form and exhibit Tl⋯S and Tl⋯π contacts (TrBs), which assist the formation of unique supramolecular polymeric architectures owing to the stereochemically active lone pair of electrons and hemi-directed coordination sphere around thallium. A differentiating feature in compound 2 is the formation of a unique Tl⋯π/π⋯π/Tl⋯π self-assembly. The attractive nature of TrB was further confirmed by DFT calculations using the quantum theory of atoms-in-molecules (QTAIM) and non-covalent interaction plot (NCIPlot) index methods. A systematic Hirshfeld surfaces analysis was also carried out to compare the intermolecular interactions. [ABSTRACT FROM AUTHOR]

Ternary thallium compound TlInSe2 exhibits a giant Seebeck effect below around 410 K, where Tl atoms form one dimensional incommensurate (IC) arrays. To clarify the origin of large thermoelectric power in the IC phase, the electronic properties of Tl-atom super-structured TlInSe2 were studied using the first-principles calculations. It was shown that the super-structures induce strong binding states between Se-p orbitals in the nearest neighboring layers and produce large density of states near lower conduction bands, which might be one of the origins to produce large thermoelectric power. [ABSTRACT FROM AUTHOR]

Ternary thallium compound TlInSe2 exhibits a giant Seebeck effect below around 410 K, where Tl atoms form one dimensional incommensurate (IC) arrays. To clarify the origin of large thermoelectric power in the IC phase, the electronic properties of Tl-atom super-structured TlInSe2 were studied using the first-principles calculations. It was shown that the super-structures induce strong binding states between Se-p orbitals in the nearest neighboring layers and produce large density of states near lower conduction bands, which might be one of the origins to produce large thermoelectric power. [ABSTRACT FROM AUTHOR]

Thallium (Tl) can be released as a byproduct of smelting, mining, and other industries, causing human exposure. There are knowledge gaps on the toxicity of thallium compounds, so the National Toxicology Program is investigating the toxicity of thallium (I) sulfate in rodents. We developed and validated a method to quantitate Tl in rodent plasma and secondary matrices. Primary matrix standards and validation samples were digested with nitric acid and analyzed for Tl by inductively-coupled plasma – mass spectrometry (ICP-MS). Method performance was validated for linearity, accuracy, precision, and other criteria. Calibration was linear from 1.25 to 500 ng Tl/mL plasma; accuracy (RE) was −5.9 to 2.6% for all calibration standards. The lower limit of quantitation (LLOQ) was 1.25 ng Tl/mL plasma, and the limit of detection was 0.0370 ng Tl/mL plasma. Intra- and interday RE and precision (RSD) were −5.6 to −1.7% and ≤0.8% (intraday) and −4.8 to −1.3% and ≤4.3% (interday), respectively, at three sample concentration levels. Standards up to 10.0 x 103 ng/mL could be analyzed by dilution with digested blank matrix, with −6.4% RE and 5.4% RSD. Method was also evaluated in post-natal day 4 (PND4) Hsd:Sprague Dawley SD (HSD) dam and pup plasma, gestation day 18 (GD 18) HSD rat fetal homogenate, HSD rat urine, female HSD rat brain homogenate, female B6C3F1 mouse plasma. Background Tl was detected in control fetal and brain homogenates and urine at < 30% of LLOQ response. Results demonstrate that the method is suitable for determination of Tl in rodent matrices for toxicology studies. [ABSTRACT FROM AUTHOR]

The vital role of triel bonding (TrB) has been highlighted in two new thallium compounds i.e. Tl+[{(4-C2H5)C6H4O}2PS2]2− (1) and Tl[{(4-CH(CH3)2)C6H4O}2PS2]2 (2). These new compounds have been characterized by elemental and spectral analyses. The crystal structures of 1 and 2 belong to the monoclinic and triclinic systems with space groups P21/c and P1¯, respectively. Interestingly, compound 1 exists in ionic form and is stabilized through intramolecular Tl⋯S (TrBs) interactions wherein the thallium atom is symmetrically positioned in the cleft of the ligand with longer Tl–S distances. In compound 2, the thallium atom is coordinated to one sulfur atom and the other sulfur atom participates in TrB interaction. Both compounds also exhibit intermolecular Tl⋯S, Tl⋯π (TrBs), and C–H⋯Tl (anagostic) interactions, which assist to form unique supramolecular architectures owing to large size as well as coordinative unsaturation on the thallium. These non-covalent TrB interactions were authenticated by Hirshfeld surface analysis (HSA) and density functional theory (DFT) calculations using the quantum theory of atoms-in-molecules (QTAIM) and non-covalent interaction plot (NCI Plot) index methods. TrBs involving Tl have been scarcely described in the literature; therefore this work provides valuable insight into the importance of these unprecedented TrBs in the solid state. [ABSTRACT FROM AUTHOR]

Lanthanum-doped high quality TlInS2 (TlInS2:La) ferroelectric-semiconductor was characterized by photo-induced current transient spectroscopy (PICTS). Different impurity centers are resolved and identified. Analyses of the experimental data were performed in order to determine the characteristic parameters of the extrinsic and intrinsic defects. The energies and capturing cross section of deep traps were obtained by using the heating rate method. The observed changes in the Thermally Stimulated Depolarization Currents (TSDC) near the phase transition points in TlInS2:La ferroelectric-semiconductor are interpreted as a result of self-polarization of the crystal due to the internal electric field caused by charged defects. The TSDC spectra show the depolarization peaks, which are attributed to defects of dipolar origin. These peaks provide important information on the defect structure and localized energy states in TlInS2:La. Thermal treatments of TlInS2:La under an external electric field, which was applied at different temperatures, allowed us to identify a peak in TSDC which was originated from La-dopant. It was established that deep energy level trap BTE43, which are active at low temperature (T≤156 K) and have activation energy 0.29 eV and the capture cross section 2.2×10-14 cm2, corresponds to the La dopant. According to the PICTS results, the deep level trap center B5 is activated in the temperature region of incommensurate (IC) phases of TlInS2:La, having the giant static dielectric constant due to the structural disorders. From the PICTS simulation results for B5, native deep level trap having an activation energy of 0.3 eV and the capture cross section of 1.8×10-16cm2 were established. A substantial amount of residual space charges is trapped by the deep level localized energy states of B5 in IC-phase. While the external electric field is applied, permanent dipoles, which are originated from the charged B5 deep level defects, are aligned in the direction of the applied electric field and the equilibrium polarization can be reached in a relatively short time. When the polarization field is maintained, while cooling the temperature of sample to a sufficiently low degrees, the relaxation times of the aligned dipoles drastically increases. Practically, frozen internal electric field or electrets states remain inside the TlInS2:La when the applied bias field is switched off. The influence of deep level defects on TSDC spectra of TlInS2:La has been revealed for the first time. [ABSTRACT FROM AUTHOR]

In this paper, investigations were carried out on the effects of simultaneous partial substitution of Tl at the Hg site on the physical properties of an Hg1- xTlxBa2Ca2Cu3O8+δ cuprate superconductor with x= 0, 0.1, 0.2, 0.3 and 0.4. Two steps of the solid state reaction method were used to prepare samples in capsule. The results showed that the optimum sintering temperature was equal to 850 ᵒC and the sintering time was equal to 20 h for the prepared samples. The best conditions for constitution and stabilization of the high Tc phase-1223 were obtained by investigating the effects of Tl substitution on Hg site and oxygen content (δ) on the superconducting properties. Structural investigation revealed that all the samples have a tetragonal structure with two phases, namely an Hg-1223 high Tc phase as a main phase and an Hg-1212 low Tc phase. Besides, some impurity phases like CuO and CaHgO2 were found. The increase of Tl content in Hg1-xTlxBa2Ca2Cu3O8+δ compound from 0 to 0.4 caused a change in the lattice parameter, density of the unit cell (ρm), and c/a values. HgBa2Ca2Cu3O8+δ compound exhibited a critical transition temperature that is equal to 115 K. On the other side, the results showed that the highest Tc was 119 K for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ. The oxygen content (δ= 0.46) was expected to be the optimum hole doping for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ compound, which means in our opinion that δ plays a remarkable role in the assessment of Tc. [ABSTRACT FROM AUTHOR]

The Li (i = l, α, β, and γ) production cross-sections, L-shell average fluorescence yields, and Coster-Kronig vacancy transfer factors for L3 subshell X-rays of thallium in some thallium compounds were determined using Energy Dispersive X-ray Fluorescence spectrometer. The compounds were excited by 59.5 keV gamma-rays from an Americium-241 annular radioactive source, and the L X-rays emitted by the compounds were counted using an ultra-low energy germanium detector with a resolution of 150 eV at 5.9 keV. The production cross-sections, average fluorescence yields, and Coster-Kronig vacancy transfer factors of thallium in these compounds were compared with theoretical calculations and available experimental values of the pure thallium. [ABSTRACT FROM AUTHOR]

We present the first implementation of the relativistic quantum chemical two- and four-component density matrix renormalization group algorithm that includes a variational description of scalarrelativistic effects and spin–orbit coupling. Numerical results based on the four-component Dirac–Coulomb Hamiltonian are presented for the standard reference molecule for correlated relativistic benchmarks: thallium hydride. [ABSTRACT FROM AUTHOR]

This theoretical study is performed to investigate structural, elastic, and electronic properties as well as optical response to incident photons of thallium based chloroperovskite TlXCl3 (X = Ca and Cd) compounds. Both compounds have a stable crystal structure with optimized lattice constants ranging from 5.40 Å to 5.26 Å. The elastic parameters such as elastic constants, bulk modulus, anisotropy factor, Poisson's ratio, and Pugh's ratio are evaluated. Poisson's ratio describes the ductile nature of these materials. The band structure and elemental contribution to different states for all the compounds are analyzed. Materials have a wide bandgap with indirect band nature. Optical parameters such as dielectric function, refractive index, extinction coefficient, reflectivity, absorption coefficient, and optical conductivity are studied in the energy range of 0 eV–30 eV. The comparative results suggest that thallium based compounds are important to be used as scintillating materials and stimulate further experimental investigations of such compounds. [ABSTRACT FROM AUTHOR]

A thallium bromide (TlBr) gamma-ray detector was developed for particle-induced gamma-ray emission (PIGE) applications. The PIGE spectrum of a lithium fluoride (LiF) crystal was obtained for the first time using the TlBr detector. This detector was fabricated using a zone-purified crystal with dimensions of approximately 2mm × 2mm × 5mm. An energy resolution of 2.3% full-width at half maximum for 511 keV gamma rays was obtained from the detector at room temperature. The LiF crystal target was irradiated with a 20 MeV proton beam at the Aomori Prefecture Quantum Science Center. Full-energy peaks of 478 keV and 197 keV were successfully detected from lithium and fluorine, respectively, using the TlBr detector in the PIGE experiment. [ABSTRACT FROM AUTHOR]

The measurements of X-ray emission lines in atomic decay to the L-shell of thallium compounds were performed using a laboratory source-based conventional wavelength dispersive spectrometer. A large set of physical fundamental parameters such as X-ray transition energies, natural linewidths and relative transition probabilities were determined by robust spectral fitting trials. The current effort presents valuable intuition about the chemical effect in distinct thallium compounds, viz., pure Tl, TlX [X = (NO3)3, I, and Cl], and Tl2X (X = O3 and SO4) on the Lp (p = l, α, η, β) X-ray lines. The investigation of chemical effects is one of the highly pressing tasks in understanding the various physical fundamental parameters in distinct metal-compounds. The results illustrate that the Lp (p = l, α, η, β) X-ray lines emitted from various thallium targets show energy shifts of ∼0.03–3.39 eV relative to the pure thallium target. In general, the outcomes of this study are consistent with the published data associated with the framework of the atomic Hartree–Fock (AHF), relativistic many-body problems in atoms and semi-empirical procedure developed within intermediate coupling calculations. For the first time, several physical fundamental parameters of thallium compounds have been investigated in this work, which are likely due to the adoption of robust spectral fitting procedures. The abruptly deviating peak profile variations found in distinct thallium-based metal-compounds can be reflected in the viewpoint of the linewidth, different electronegativity values of adjacent ligands, effective charge, changes in the transition probability, mixed oxidation states of thallium and valence to core exchange interactions. Furthermore, in the current study, the possible connection among X-ray line shifts and parameters are systematically scrutinised. [ABSTRACT FROM AUTHOR]

We analyzed the transient absorption properties of TlBr crystals using pulsed electron beams as excitation sources. We observed transient absorption spectra and temporal profiles on the pico- and nanosecond scales and compared the results obtained for TIBr crystals that are empirically appropriate with those that are inappropriate for semiconductor detectors. The results showed negligible differences in properties between the two types of crystal, which indicates that their trap center concentrations were similar. A transient absorption band was observed at approximately 1160 nm on the nanosecond scale, while its short-wavelength tail was observed on the picosecond scale. The absorption band is attributed to the localized holes at Tl+ that are stabilized by some defects. In contrast, no absorption band attributable to localized electron centers was observed, indicating that while hole transport is hindered by defects, electron transport is not [ABSTRACT FROM AUTHOR]

The title compound represents the thallium(I) salt of a substituted 1,2,5-oxadiazole, [Tl(C3H3N4O3)]n, with amino- and hydroxamate groups in the 4- and 3- positions of the oxadiazole ring, respectively. In the crystal, the deprotonated hydroxamate group represents an intermediate between the keto/enol tautomers and forms a five-membered chelate ring with the thallium(I) cation. The coordination sphere of the cation is augmented to a distorted disphenoid by two monodentately binding O atoms from two adjacent anions, leading to the formation of zigzag chains extending parallel to the b axis. The cohesion within the chains is supported by π-π stacking [centroid-centroid distance = 3.746-(3)-Å] and intermolecular N-H···N hydrogen bonds. [ABSTRACT FROM AUTHOR]

I use electronic structure calculations based on a newly developed functional that is designed to reliably predict band structure and band gaps of semiconductors to investigate the electronic structures and optical properties of TlPbI3, TlGeI3, and TlSnI3. The results indicate that TlPbI3 if activated may be a potentially useful low band gap scintillator. The possibility of using Sn as an activator is investigated. [ABSTRACT FROM AUTHOR]

Spectroscopic ellipsometry measurements were carried out on TlSe single crystals for orientations of electric field, parallel (E∥c), and perpendicular (E⊥c) to optic axis c. The experiments were performed in the 1.2-6.2 eV spectral range at room temperature. The real and imaginary parts of the pseudodielectric function as well as pseudorefractive index and pseudoextinction coefficient were calculated from the analysis of ellipsometric data under the light of ambient-substrate optical model. The energies of interband transitions (critical points) have been found from the analysis on second derivative spectra of the pseudodielectric function. The analysis revealed four and five interband transition structures for E∥c and E⊥c configurations, respectively. The obtained critical point energies were assigned tentatively to interband transitions using the available electronic energy band structure given in literature. [ABSTRACT FROM AUTHOR]

The structural, electrical, and thermal properties of the ferroelectric-semiconductor TlGaSe2 have been investigated after the thermal annealing of crystals inside the incommensurate (INC) phase for a few hours at the annealing temperature (Tann). It is found that all outlined physical parameters of TlGaSe2 are significantly modified after the annealing process. Besides the well-known memory effect, thermal annealing within the INC phase leads to previously unknown anomalies of the different physical properties of TlGaSe2 crystals at temperatures quite far from the INC-phase. To explain the experimental results it is supposed that annealing leads to the formation of a new polarized state that influences most of the physical parameters of the crystals. This outstanding feature of the annealing effect in TlGaSe2 crystals allows us to reveal some new phase transitions that take place in TlGaSe2 crystals in the 140-180 K temperature range. [ABSTRACT FROM AUTHOR]

We present the results of a detailed experimental study of polarization effects in thallium bromide planar x-ray detectors. Measurements were carried out in the range 10-100 keV by scanning a highly focused x-ray beam, 50 μm in diameter, from a synchrotron source across the detector. Above a certain radiation threshold the detector response showed a systematic degradation of its spectroscopic characteristics, peak channel position, peak height, and energy resolution. Using a pump-and-probe technique, we studied the dynamics of spectral degradation, the spatial extent and relaxation of the polarized region, and the dependence of the detector response on bias voltage and temperature. For comparison, we modeled polarization effects induced by the charging of traps by both electrons and holes using a model based on recent theoretical work of Bale and Szeles. We calculated the charge collection efficiency and spectral line shapes as functions of exposure time, beam position, count rate, and photon energy, and obtained credible agreement with experimental results. [ABSTRACT FROM AUTHOR]

First-principles calculations are carried out to study the native defect properties in TlBr. Three important results emerge: (1) the native defects are benign in terms of electron trapping because the low-energy defects do not induce electron traps; (2) the dominant defects in nearly stoichiometric TlBr are Schottky defects that pin the Fermi level near the midgap, leading to high resistivity; and (3) the calculated low diffusion barriers for several native defects show that ionic conductivity can occur at room temperature. The important impacts of these material properties on the room-temperature radiation detection using TlBr are discussed. [ABSTRACT FROM AUTHOR]

The authors tried to enhance the thermoelectric figure of merit of AgTlTe with extremely low thermal conductivity by controlling the carrier concentration. Pd- or Cu-doped AgTlTe was prepared and characterized. Pd did not dissolve in AgTlTe, whereas Cu fully dissolved up to x=0.4 in Ag1-xCuxTlTe. The effect of Cu doping was investigated by measuring the thermoelectric properties of polycrystalline Ag1-xCuxTlTe (x=0-0.4) from room temperature to slightly below the melting temperature. Cu doping resulted in a net increase in the hole concentration of AgTlTe. Cu doping improved the power factor of AgTlTe while keeping the thermal conductivity extremely low, leading to an enhancement of the thermoelectric figure of merit. [ABSTRACT FROM AUTHOR]

Over the past decade, the physics of low-dimensional materials beyond graphene has been of significant interest to both science and applications. To this end, we report on the nuclear magnetic resonance (NMR) study of the layered two-dimensional compound of thallium monosulfide TlS. The structure of this semiconductor compound consists of the metal-chalcogen layers formed by Tl3+S 4 2− tetrahedra and chains of univalent Tl1+ ions between the layers. 205Tl NMR measurements reveal phase transitions at 262, 305, 319, 341, and 350 K. In the regions 319–341 K and 262–305 K, the temperature dependence of spin-lattice relaxation time shows plateaus characteristic of incommensurate phases. The results obtained, as well as the microscopic origin of phase transitions are discussed along with literature data on dielectric and X-ray measurements and the electronic structure of the TlS. [ABSTRACT FROM AUTHOR]

We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3 (M=Zr, Hf; Q=S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, Tl2ZrTe3 and Tl2HfTe3 can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second-order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications (). [ABSTRACT FROM AUTHOR]

A new compound thallium ammonium sulfate selenate tellurate: Tl0.92(NH4)0.08(SO4)0.65(SeO4)0.35Te(OH)6 (TlNSSeTe) has been synthesized by slow evaporation at room temperature to specify its phase transition temperatures. X-ray diffractometry data revealed crystallization in the monoclinic system with a P21/c space group with these parameters: a = 12.336(2) Å, b = 7.2038(14) Å, c = 12.017(2) Å et β = 110.631(10)°, V = 999.4(3) Å3 and Z = 4. Three coexisting anions (TeO66-, SO42- and SeO42-) are the main characteristics of these atomic arrangements in the unit cell, related by O-H...O and N-H...O bonds building up the crystal. The cations Tl+ and NH4+ lie at the same positions between these polyhedra. The new synthesized compound has been characterized by using the differential scanning calorimetry (DSC), thermal analysis [differential thermogravimetric analysis (TG), as well as thermodifference analysis (DTA)], FT-IR and Raman spectroscopy techniques. The DSC results demonstrated phase transitions at 384 K, 465 K and 472 K. DTA and TG proved that decomposition takes place in three steps. The vibrational spectroscopy study at room temperature unveiled not only the occurrence and the independence of anionic and cationic groups, but also the importance of the hydrogen bonds. [ABSTRACT FROM AUTHOR]

A new compound thallium ammonium sulfate selenate tellurate: Tl0.92(NH4)0.08(SO4)0.65(SeO4)0.35Te(OH)6 (TlNSSeTe) has been synthesized by slow evaporation at room temperature to specify its phase transition temperatures. X-ray diffractometry data revealed crystallization in the monoclinic system with a P21/c space group with these parameters: a = 12.336(2) Å, b = 7.2038(14) Å, c = 12.017(2) Å et β = 110.631(10)°, V = 999.4(3) Å3 and Z = 4. Three coexisting anions (TeO66-, SO42- and SeO42-) are the main characteristics of these atomic arrangements in the unit cell, related by O-H...O and N-H...O bonds building up the crystal. The cations Tl+ and NH4+ lie at the same positions between these polyhedra. The new synthesized compound has been characterized by using the differential scanning calorimetry (DSC), thermal analysis [differential thermogravimetric analysis (TG), as well as thermodifference analysis (DTA)], FT-IR and Raman spectroscopy techniques. The DSC results demonstrated phase transitions at 384 K, 465 K and 472 K. DTA and TG proved that decomposition takes place in three steps. The vibrational spectroscopy study at room temperature unveiled not only the occurrence and the independence of anionic and cationic groups, but also the importance of the hydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract Thallium is among the most toxic elements to humans. Environmental regulations of the European Community adopted by Italy pose a maximum concentration level for Tl in groundwater of 2 μg/L. However, at present drinkable water must not abide any concentration threshold for thallium and this element is not routinely monitored. In the past-mining area nearby the Valdicastello Carducci village (northern Tuscany, Italy), characterized by Tl-bearing ores, water from a spring that has been tapped for human consumption contains thallium in the range 4.3–27.8 μg/L. The challenge of this study is to highlight the mechanisms leading to Tl contamination in groundwater, by crossing hydrochemical and O-H isotopic data with hydrogeological information. We propose that the Tl-contamination in the spring results from a binary mixing that occurs within a karst system involving an uncontaminated Ca-HCO 3 water (mainly interacting with limestone) and a component originated by the interaction of acid drainages (generated by the weathering of Tl-bearing mineral phases in the area) with dolomitic host rocks. In this process, most of the potentially toxic elements released during the weathering are scavenged by the carbonate neutralization of the acid plume due to adsorption onto the iron and manganese oxyhydroxides that formed during pH changes. Nevertheless, the aquifer has little or no attenuation capacity for thallium. Moreover, O-H isotopic data and hydrogeological constraints are compatible with a spring feeding mechanism related to a piston displacement effect. Highlights • Water from a spring that has been tapped for human consumption contains thallium. • The Tl contamination in the spring results from mixing of different reservoirs. • One reservoir is formed by the interaction of acid drainages with carbonate rocks. • Most of the metals but thallium are scavenged subsequently to neutralization of the acid plume. [ABSTRACT FROM AUTHOR]

Abstract A new multivariate standard addition strategy applicable to stripping methods was proposed as an extention of the classical univariate standard addition method for the resolution of complex samples involving overlapped peaks and complex matrices. The proposed strategy consists in alternate additions of the considered analytes and the further extrapolation to a simulated blank solution measured by skipping the preconcentration step (deposition time = 0). This calibration approach was successfully tested in tonic water samples spiked with Tl(I) and In(III) using a sensor array based on a SeCyst-SPCNFE and an ex-situ- BiSPCE, providing good concordance between replicates and much better accuracy than the usual multivariate external calibration method. Graphical abstract fx1 Highlights • A new multivariate standard addition strategy for stripping methods is developed. • The approach is based on the removal of the accumulation step (t d = 0) to simulate a true blank solution. • The methodology has been successfully tested in tonic water samples spiked with Tl(I) and In(III) using a sensor array based on a SeCyst-SPCNFE and an ex-situ -BiSPCE. [ABSTRACT FROM AUTHOR]

Abstract Recently, chalcogenides materials that containing sulfur, S, have attracted scientists attention for using as active recording films in programmable metallization cell memory (PMC) devices. Thus, in the present work a nanostructured TlInS 2 thin film is prepared by using thermal evaporation and is characterized via X-ray diffractometer (XRD) and transmission electron microscope (TEM). Based on XRD calculations and TEM micrograph, the as-deposited thin film shows nanostructure of average particle size equals to 50 ± 4 nm. Subsequently, a device of the structure Au/TlInS 2 /Au is fabricated using thermal evaporation and is investigated by using impedance spectroscopy. The DC electrical conductivity is carried out in the temperature range of 358–468 K. The AC electrical and dielectric properties are measured in the dark conditions and their dependence on the temperature (373–473 K) and the frequency (0.5–200 kHz) is discussed. Of these, the σ ac increases as the temperature increases and it obeys the universal power law σ ac = Aωs. Also, the dielectric constants show high values at high temperatures due to the presence of interface charges that is formed at the interfacial surface between the gold electrode and TlInS 2 NPs. Moreover, the real part of the dielectric modulus M' reveals low values at low frequencies and it increases as frequency increases and this is interpreted in terms of the disability of driving forces (at low frequencies) which governs the mobility of charge carriers under the influence of the electric field. Graphical abstract Image 1 Highlights • TlInS 2 thin film is successfully prepared via thermal evaporation. • Nanostructure of the film is confirmed via XRD technique and TEM image. • Electrical and dielectrical properties of the sandwiched structure are investigated. • Charge transfer at metal/semiconductor interface is discussed. • Conduction mechanism is explained in terms of VRH and CBH models. [ABSTRACT FROM AUTHOR]