Results of this research are available online in two published papers. / The main focus of this research was to synthesize and then to characterize the potential high-performance thermoelectric materials. In this regard, we have prepared a series of pure RECuSe2 (with RE = Pr, Sm, Gd, Dy and Er) and RECuTe2 (with RE = Er, Dy and Gd) and analyzed their crystal structure, electronic and physical properties. We used powder and single crystal X-ray diffraction techniques to analyze their crystal structures and employed energy dispersive X-ray spectrometry (EDS) to verify their chemical compositions. The temperature stability of the synthesized samples was examined by differential thermal and gravimetrical analysis. The high-purity consolidated pellets were prepared for physical properties measurements. We analyzed the relationship between their crystal structures and pertinent electronic properties through the LMTO calculations. The RECuSe2 phases adopt two structures, monoclinic and trigonal. The monoclinic structure (P21/c, z = 4) is observed for lighter rare earths (RE = Pr, Sm and Gd) and Cu-disordered trigonal structure for heavier rare earths (P m1, z = 1, RE = Dy and Er). The resistivity and Seebeck coefficient measurements indicate that the studied selenides are p-type semiconductors with relatively small activation energies (0.045-0.12 eV). However, their electrical resistivities are too high (0.49-220 Ohmcm at room temperature) to make them competitive thermoelectric materials. Electronic structure calculations indicate presence of a band gap in the RECuSe2 phases. The synthesized RECuTe2 phases (RE = Er, Dy and Gd) adopt a monoclinic-distorted variant (C2/m, z = 2) of the trigonal structure (P m1, Z= 1) observed for the RECuSe2 (with RE = Dy, Er). While such disorder may be beneficial for lowering their thermal conductivity, large values of electrical resistivity (0.02-0.87 Ohmcm at room temperature) make these phases unsuitable for practical applications. Comparing to the corresponding semiconducting selenides, the tellurides have lower resistivities, and display a metallic type resistivity. Such behavior stems from the closure of band gaps, which is verified by the electronic structures calculations. Structurally the RECuTe2 phases (with RE = Er, Dy and Gd) are similar to RECuSe2 with the P m1 structure. The monoclinic distortion in RECuTe2 is driven by Cu displacement inside the larger tetrahedral voids in the hexagonal close packing of the Te atoms. Most likely, Cu shifts to one side of the Te tetrahedra to optimize the Cu-Te interactions. / Thesis / Candidate in Philosophy

The addition of rare earth (RE) alloying elements is a promising method for improving the strength, ductility and overall formability of magnesium (Mg) alloys. However, the underlying mechanism for this phenomenon remains unclear. An investigation on the effect of the rare earth element, scandium (Sc), on binary Mg-Sc alloys has been pursued. Tension and compression tests were performed on a series of dilute binary Mg-Sc alloys at temperatures of 298 K, 78 K and 4.2 K. As a reference, pure Mg was also investigated for comparative purposes. Differences in tension and compression stress-strain curves highlighted distinct activated mechanisms, where slip dominated in tension and twinning governed compression. The observed increase in ductility and prolonged necking was attributed to a weaker basal texture, enhanced twinning and non-basal slip. A decreased work hardening rate suggests an improvement in dislocation recovery with Sc addition. In compression, Mg-Sc alloys followed Fleischer’s theory of solution hardening, where stress scales with concentration, c, as c^1/2; however, there was a very weak fit with both Fleischer and Labusch models under tension. The strengthening rate displayed by Mg-Sc was relatively weak compared to previously studied Mg-RE systems. However, considering the estimated misfit parameters, the size and modulus misfit was not enough to account for the strengthening rate. The results suggest that hardening of the twinning mode may influence strength. Constitutive modelling, based on a self-consistent plasticity model, was used to characterize the deformation behaviour. The simulations predicted an increased relative activity of non-basal <c+a> slip with Sc addition, supporting experimental results and proposed mechanisms in literature. The results of Mg-Sc alloys have been connected to theories that identify a decrease in stacking fault energy (SFE) as the determining factor for increased strength and ductility of Mg-RE alloys. A comparison of the SFE of previously studied REEs with Sc, demonstrated strong evidence towards the theory’s validity. Sc has been shown to only moderately reduce the SFE of Mg and hence, the present experimental results have shown a moderate increase in strength and ductility. Additional modelling and detailed dislocation analysis are suggested as future steps to further support this theory. / Thesis / Master of Applied Science (MASc)

Up-conversion (UC) in rare-earth co-doped fluorides to convert diode laser light in the near infrared to red, green and blue visible light is applied to make possible high performance emissive displays. The infrared-to-visible UC in the materials we study is a sequential form of non-linear two photon absorption in which a strong absorbing constituent absorbs two low energy photons and transfers this energy to another constituent which emits visible light. Some of the UC emitters' most appealing characteristics for displays are: a wide color gamut with very saturated colors, very high brightness operation without damage to the emitters, long lifetimes and efficiencies comparable to those of existing technologies. Other advantages include simplicity of fabrication, versatility of operating modes, and the potential for greatly reduced display weight and depth. Thanks to recent advances in material science and diode laser technology at the excitation wavelength, UC selected materials can be very efficient visible emitters. However, optimal UC efficiencies strongly depend on chosing proper operating conditions. In this thesis, we studied the conditions required for optimization. We demonstrated that high efficiency UC depends on high pump irradiance, low temperature and low scattering. With this understanding we can predict how to optimally use UC emitters in a wide range of applications. In particular, we showed how our very efficient UC emitters can be applied to make full color displays and very efficient white light sources.

Density Functional Theory (DFT) method is applied to study the crystal structure of transition metal and lanthanide oxides, as well as molecular magnetic complexes. DFT is a widely popular computational approach because it recasts a many-body problem of interacting electrons into an equivalent problem of non-interacting electrons, greatly reducing computational cost. We show that for certain structural properties like phase stability, lattice parameter and oxygen migration energetics pure DFT can give good agreement with experiments. But moving to more sensitive properties like spin state energetic certain modifications of standard DFT are needed. First we investigated mixed ionic-electronic conducting perovskite type oxides with a general formula ABO3 (where A =Ba, Sr, Ca and B = Co, Fe, Mn). These oxides often have high mobility of the oxygen vacancies and exhibit strong ionic conductivity. They are key materials that find use in several energy related applications, including solid oxide fuel cell (SOFC), sensors, oxygen separation membranes, and catalysts. Different cations and oxygen vacancies ordering are examined using plane wave pseudopotential density functional theory. We find that cations are completely disordered, whereas oxygen vacancies exhibit a strong trend for aggregation in L-shaped trimer and square tetramer structure. On the basis of our results, we suggest a new explanation for BSCF phase stability. Instead of linear vacancy ordering, which must take place before the phase transition into brownmillerite structure, the oxygen vacancies in BSCF prefer to form the finite clusters and preserve the disordered cubic structure. This structural feature could be found only in the first-principles simulations and cannot be explained by the effect of the ionic radii alone. In order to understand vacancy clustering and phase iv stability in oxygen-deficient barium strontium cobalt iron oxide (BSCF), we predict stability and activation energies for oxygen vacancy migration. Using symmetry constrained search and Nudged Elastic Band method, we characterize the transition states for an oxygen anion moving into a nearby oxygen vacancy site that is surrounded by different cations and find the activation energies to vary in the range 30-50 kJ/mol in good agreement with experimental data. Next we study spin alignments of single molecule magnets (SMM). SMMs are a class of polynuclear transition metal complexes, which characterized by a large spin ground state and considerable negative anisotropy. These properties lead to a barrier for the reversal of magnetization. For these reasons SMM are expected to be promising materials for molecular spintronics and quantum computing applications. To design SMM for quantum computation, we need to accurately predict their magnetic properties. The most important property is, Heisenberg exchange coupling constant (J). This constant appears in model Heisenberg Hamiltonian that can be written in general form as here Jij represents the coupling between the two magnetic centers i and j with the spin states Si and Sj. The positive J values indicate the ferromagnetic ground state and the negative ones indicate the antiferromagnetic ground state. We found pure DFT is not accurate enough to predict J values. We employ density functionals with a Hubbard U term that helps to counteract the unphysical delocalization of electrons due to errors in pure exchange-correlation functionals. Unlike most previous DFT+U studies, we calibrate U parameters for both metal and ligand atoms using five binuclear manganese complexes as the benchmarks. We note delocalization of the spin density onto acetate ligands due to π-back bonding, inverting spin-polarization of the Jiij −= ∑ S.S.JH v acetate oxygen atoms relative to that predicted from superexchange mechanism. This inversion may affect performance of the models assuming strict localization of the spins on magnetic centers for the complexes with bridging acetate ligands. Next, we apply DFT+U methodology for Mn12(mda) and Mn12(ada) complexes to calculate all six nearest neighbor Jij value. Our result shows both qualitative and quantitative agreement with experiments unlike other DFT studies. Using the optimized geometry of the ground spin state instead of less accurate experimental geometry was found to be crucial for this good agreement. The protocol tested in this study can be applied for the rational design of single-molecule magnets for molecular spintronics and quantum computing applications. Finally we apply hybrid DFT methodology to calculate geometrical parameters for cerium oxides. We review the experimental and computational studies on the cerium oxide nanoparticles, as well as stoichiometric phases of bulk ceria. Electroneutral and nonpolar pentalayers are identified as building blocks of type A sesqioxide structure. The idealized structure of the nanoparticles is described as dioxide covered by a single pentalayer of sesquioxide, which explains the exceptional stability of subsurface vacancies in nanoceria. The density functional theory (DFT) predictions of the lattice parameters and bulk moduli for the Ce(IV) and Ce(III) oxides at the hybrid DFT level are also presented. The calculated values for both compounds agree with experiment and allow to predict changes in the lattice parameter with decreasing size of the nanoparticles. The results validate hybrid DFT as a promising method for future study the structure of oxygen vacancies and catalytic properties of ceria nanoparticles.

Froth flotation has long been regarded as the best available technology for ultrafine particles separation. However, froth flotation has extreme deficiencies for recovering ultrafine particles that are less than 30-50 μm in size for coal and 10-20 μm for minerals. Furthermore, dewatering of flotation products is difficult and costly using currently available technologies. Due to these problems, coal and mineral fines are either lost to tailings streams inadvertently or discarded purposely prior to flotation. In light of this, researchers at Virginia Tech have developed a process called hydrophobic-hydrophilic separation (HHS), which is based originally on a concept known as dewatering by displacement (DbD). The process uses non-polar solvents (usually short-chain alkanes) to selectively displace water from particle surfaces and to agglomerate fine coal particles. The resulting agglomerates are subsequently broken (or destabilized) mechanically in the next stage of the process, whereby hydrophobic particles are dispersed in the oil phase and water droplets entrapped within the agglomerates coalesce and exit by gravity along with the hydrophilic particles dispersed in them. In the present work, further laboratory-scale tests have been conducted on various coal samples with the objective of commercial deployment of the HHS process. Test work has also been conducted to explore the possibility of using this process for the recovery of ultrafine minerals such as copper and rare earth minerals. Ultrafine streams produced less than 10% ash and moisture consistently, while coarse coal feed had no observable degradation to the HHS process. Middling coal samples were upgraded to high-value coal products when micronized by grinding. All coal samples performed better with the HHS process than with flotation in terms of separation efficiency. High-grade rare earth mineral concentrates were produced with the HHS process ranging from 600-2100 ppm of total rare earth elements, depending on the method and reagent. Additionally, the HHS process produced copper concentrates assaying greater than 30% Cu for both artificial and real feed samples, as well as, between 10-20% Cu for waste samples, which all performed better than flotation. / Master of Science / Froth flotation has long been regarded as the best available technology for separating fine particles. Due to limitations in particle size with froth flotation, and high downstream dewatering costs, a new process has been developed called the hydrophobic-hydrophilic separation (HHS) process. This process was originally based on a concept known as dewatering by displacement (DbD) which was developed by researchers at Virginia Tech in 1995. The process uses hydrocarbon oils, like pentane or heptane, to selectively collect hydrophobic particles, such as coal, for which it was originally developed. In coal preparation plants, a common practice is to purposefully discard the ultrafine stream that flotation cannot recover and has an increased dewatering cost. The HHS process can effectively recovery this waste stream and produce highgrade salable product, with significantly reduced cost of dewatering. In the work presented, laboratory-scale tests have been conducted on various coal samples with the objective of commercial deployment of the HHS process. In this respect, several varying plant streams have been tested apart from the traditional discard stream. Additionally, test work has expanded into mineral commodities such as copper and rare earth minerals. In this work, salable high-value coal products were achievable with the HHS process. Ultrafine streams consistently produced less than 10% ash and moisture. Coarse coal feeds had no observable degradation to the HHS process and were able to produce single digit ash and moisture values. Middling coal samples were upgraded to high-value coal products when micronized by grinding. All coal samples performed better with the HHS process than with flotation in terms of separation efficiency. High-grade rare earth mineral concentrates were produced with the HHS process ranging from 600- 2100 ppm of total rare earth elements depending on the method and reagent. Additionally, the HHS process produced copper concentrates assaying greater than 30% Cu for an artificial and feed samples, as well as, between 10-20% Cu for waste samples, which all performed better than flotation.

The field of analytical chemistry is very important to today's society as more and more regulations and legislations emerge regarding trace elements in food, consumer products, medicines, and the environment. Like many areas of science, the current goals of trace elemental measurements and speciation are to increase knowledge on the subject and to improve upon current techniques by enhancing the figures of merit, such as accuracy and reproducibility, meanwhile balancing with the cost and time of analysis. The topics covered in this work were investigated primarily through the use of inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). The phenomenon of compound-dependent responses in plasma spectrometry is discussed, seeking possible causes of it and offering some advice on how to prevent it. A new method was developed for the speciation of selenium in dietary supplements using anion-exchange chromatography ICP-MS. A novel method for the determination of total mercury at trace concentrations in rice was developed for use with conventional ICP-MS. Inductively coupled plasma mass spectrometry was also used for fingerprinting the rare earth elements in Maya archaeological pottery for provenance studies.

Resource recovery has become essential to compensate for costly and complex technical requirements to implement zero-liquid discharge (ZLD) policies. Antiscalant removal, especially phosphonate-based antiscalants, is a clear example of resource and potential subsequent valorization. The global market for phosphonate-based antiscalants is expected to grow in the coming years along with increasing membrane desalination projects. It implies the disposal in surface waters of tons of phosphonates and trace elements, present in wastewater and concentrates, every day. Removing the phosphonates and trace elements allows their subsequent recovery and valorization, minimizing squeezing produc-tion/extraction procedures and saving the environment from suffering any im-pact because of them. The first part of this thesis focuses on phosphonate removal with iron and aluminum-based adsorbents. Porous iron and aluminum (oxi)hydroxides can remove phosphonates from concentrates completely. The main limitation of this process is the diffusion of the phosphonates through adsorbent particles. As proved in this thesis, temperature significantly improves the adsorption kinetics of the phosphonates on both adsorbents as a result of the variation of the diffusion coefficient. The presence of calcium also plays an important role, since accelerates the adsorption at the first stages of the process, but limits and saturates the capacity of the adsorbent surface for further adsorption. More research on the role of calcium is needed in this regard to better understand how the adsorption/diffusion of the phosphonates is affected by this common element present in concentrates. Electrocoagulation was studied in the second part of this thesis as a potential approach for phosphonate removal. Using pure iron electrodes, the applied current density can be easily optimized. As a result, dissolved phosphonates are quickly removed from a large concentrate volume at a relatively low cost and minimal sludge production. The benefits of this technique lie in the possibility of producing the substrate (adsorbent) in situ for the phosphonate to be adsorbed. Furthermore, the time required to completely remove the phosphonates is remarkably shorter compared to adsorption, which, as pointed out above, is limited by diffusion phenomena. Alkaline washing was relatively successful at recovering the phosphorus from the sludge, depending on the dissolved phosphonate in the concentrate. Although experimental results may look promising, further research on finding the optimum working conditions has to be addressed. The process is open to improvement in terms of new electrode materials, reactor design, phosphorus recovery, or optimal working temperature. In the third part of the thesis, the adsorption potential of previously tested adsorbents for the removal of elements at trace levels. The iron-based adsorbent, commercialized for phosphate and arsenic removal, turned out to be excellent at removing transition metals (TM) and rare earth elements (REE). The study was carried out in parallel with the exploration of the capabilities of a high-resolution inductively coupled plasma mass spectrometry (HR ICP-MS) instrument. The potential of this analytical procedure allows the detection and quantification of all the isotopes at the ultra-trace level (in the range of a few ng·L-1) and in only one measurement round. Furthermore, interferences from polyatomic species, formed during the ionization in the plasma, are easily resolved due to the high-resolution mode. As a result, the detection of the targeted element is easily discriminated from the potential interferences. This feature makes a remarkable difference regarding ordinary ICP-MS, which requires different analytical procedures to properly resolve overlapping signals. This analytical procedure opens new possibilities to test the adsorbents in new conditions and develop analytical methods for water speciation.

Rare earth elements (REEs) are critically important for high-tech, renewable energy and defense industries. However, rare earth minerals (REMs) are stable compounds, requiring aggressive conditions to decompose them for their extraction and use. One exception is the ion-adsorption clays (IACs) that are mined in South China. They were formed in nature via the adsorption of the REE ions on clay minerals; therefore, they can be readily extracted into solution under mild conditions using the ion-exchange leaching process using (NH4)2SO4 as lixiviant. It also happens that IACs are the largest source of the heavy rare earth elements (HREEs) that are critical, especially for the defense industry. At present, more than 80% of the HREEs are produced commercially from the IACs mined in Southeast Asia. The objective of the present research was to study the fundamental mechanisms involved in the formation and processing of IACs using the ion-change leaching process. The first part of the project was the synthesis of IACs by contacting kaolinite samples with known concentrations of rare earth chloride (REECl3) solutions at different pHs and analyzing the synthetic IACs for XPS studies. It was found that the REE adsorption on kaolinite stays constant in acidic pHs. At pH 7 and above, adsorption density increases sharply, possibly due to the formation of REE(OH)3 and/or REE(OOH). The IACs formed under these conditions responded well to the ion-exchange leaching process by reducing the pH to below 7. In the second part of the study, the effect of iron (Fe3+) species co-adsorbing with REEs on the kaolinite surface was studied. Unlike the colloidal phases of IACs formed at pH > 7, the synthetic IACs formed in the presence of iron did not respond to the ion-exchange leaching process using (NH4)2SO4 as lixiviant. This problem has been solved by subjecting the synthetic IACs to a reducing condition to convert the Fe3+ to soluble Fe2+ species at pH < 7. The driving force for the standard exchange leaching process is the large differences between the hydration enthalpies of the Ln3+ ions that are in the range of -3,400 kJ/mole and that of the NH4+ ions (-320 kJ/mole). In the present work, alkylammonium ions (CnH2nNH4+) of varying chain lengths were used as novel lixiviants and obtained excellent results. Since these are surface active species, their concentrations in the vicinity of the clay minerals that are negatively charged would be substantially higher than in the bulk. As a result, it was possible to achieve the same level of leaching efficiencies as obtained using ammonium sulfate at approximately ten times lower reagent dosages. One of the problems associated with extracting REEs from coal-based clays is that the REE concentrations are typically in the range of 300 to 600 ppm, which makes it difficult to extract the critical materials economically using ion-exchange leaching and other processes. As a means to overcome this issue, the REE-bearing particles, including IACs and REMs, were liberated by blunging and subsequently upgraded using the hydrophobic-hydrophilic separation (HHS) process. The results showed that blunging outperformed grinding in liberating the REE-bearing particles from the clayey materials in coal. It was shown that one can improve blunging by increasing the disjoining in the thin liquid films present between clay and other minerals by controlling the double-layer (EDL) forces. These findings should enhance our understanding of the fundamental mechanisms involved in upgrading critical materials and thereby increase the economic viability of REE recovery from coal-based materials. / Doctor of Philosophy / Rare earth elements (REEs) play a vital role in numerous modern industries, advanced technological applications, and defense industries. The United States accounts for about 15 % of the global demand for REEs. However, the country heavily relies on imported Chinese raw materials, creating vulnerability in the U.S. supply chain. REEs are rarely found in concentrations suitable for mining, and in certain cases, extracting and processing conventional REE deposits come with significant environmental hazards. The limited availability of rare earth elements (REEs) raises concerns regarding their production despite their critical role in high-tech industries. Consequently, various federal agencies and private enterprises have recently attempted to identify promising alternative resources due to these complex challenges. REEs have been found in several major coal basins and are evidenced to be associated with coal byproducts such as kaolinite clays–one of the major host materials of IACs. This research investigates the recovery of rare earth elements (REEs) from clayey materials through various processes. Emphasis is placed on the synthesis of ion-adsorption clays from kaolinite, and the factors influencing the ion-exchange leaching process are being studied. Furthermore, the impact of iron co-adsorption on REE binding to kaolinite is being examined, and reductive leaching is being evaluated as a means to overcome the hindrance caused by iron passivating layers. Novel lixiviants are being tested as alternatives to conventional lixiviant ((NH4)2SO4) for REE extraction. The application of hydrophobic-hydrophilic separation techniques for extracting REE-bearing particles from coal clay samples is also being explored, with a comparison made between grinding and blunging processes. Overall, valuable insights into the efficient recovery of REEs from clay minerals are being obtained, contributing to the development of cost-effective and novel approaches for their extraction.

The Parkin group has recently synthesized tris[(1-isopropylbenzimidazol-2-yl)dimethylsilyl]methane, [TismPriBenz]H, a bulky tetradentate tripodal ligand, which upon deprotonation can coordinated to form a variety of carbatrane metal complexes.The [TismPriBenz] ligand has been previously shown to stabilize metal hydride complexes, for example [TismPriBenz]MgH and [TismPriBenz]ZnH, and the ligand also has been incorporated in complexes featuring all of the non-radioactive Group 12 and Group 13 metals, as well as a large range of transition metals. However, the reactivity of these complexes towards carbonyl compounds is largely unexplored. Additionally, beyond [TismPriBenz]Li, there has been no attempt to introduce the heavier alkali metals into the [TismPriBenz] framework, which could potentially provide more reactive starting materials to generate other previously inaccessible metal complexes of the ligand; for instance, prior to this report, there has been no example of a lanthanide complex of [TismPriBenz]. In Chapter 1, the reactivity of [TismPriBenz]MgH and [TismPriBenz]MgMe towards ketones, aldehydes, and esters is explored. Generally, these magnesium complexes are able to insert a C=O double bond into a Mg–Me or Mg–H bond respectively, providing access to a large class of magnesium alkoxides. Specifically, [TismPriBenz]MgR (R = H, Me) can insert benzaldehyde and benzophenone to give [TismPriBenz]MgOCRHPh or[TismPriBenz]MgOCRPh₂ respectively. Additionally, [TismPriBenz]MgMe has shown rare reactivity towards methyl ketones, in that it forms the magnesium enolate compounds [TismPriBenz]MgC(Me)=CH₂ and [TismPriBenz]MgC(Ph)=CH2 upon treatment with acetone or acetophenone. In fact, [TismPriBenz]MgC(Me)=CH₂ is only the fourth acetone enolate complex to be structurally characterized, and the first such magnesium example. In the presence of the ester compounds methyl formate and ethyl acetate, [TismPriBenz]MgH and [TismPriBenz]MgMe are able to follow the insertion of the carbonyl with immediate elimination of either an aldehyde or ketone to yield the simple alkoxides [TismPriBenz]MgOMe and [TismPriBenz]MgOEt, a reaction with little precedence in the literature. [TismPriBenz]MgMe is also able to prompt the Claisen condensation of ethyl acetate, forming the first [TismPriBenz] complex with a 6-member chelating ring, [TismPriBenz]Mg(κ²-OC(Me)HC(O)OEt). These various alkoxides have demonstrated the ability to catalyze the Tishchenko reaction, the dimerization of an aldehyde to make an ester, and have also shown promise as catalysts for hydroboration and retro-aldol reactions. Lastly, the [TismPriBenz]Mg compounds have shown interesting reactivity towards O₂, leading to the isolation of both the rare peroxide dimer {[TismPriBenz]Mg}₂(μ-O₂) and the alkyl peroxide [TismPriBenz]MgOOMe. In Chapter 2, the reactivity of the complex [TismPriBenz]Tl is further developed, providing access to previously known methyl and iodide compounds of magnesium, zinc, and cadmium. Additionally, [TismPriBenz]Tl has been shown to react directly with the alkali metals sodium, potassium, and rubidium to form the novel alkali metal complexes [TismPriBenz]M (M = Na, K, Rb). Furthermore, [TismPriBenz]Li can react with CsF to afford [TismPriBenz]Cs, completing the non-radioactive Group 1 [TismPriBenz]M series. This makes [TismPriBenz] one of only a handful of organic ligands to have structurally characterized compounds with all of the alkali metals from Li to Cs, and the only ligand that formsmonomeric complexes in each case. [TismPriBenz]K was also used as a starting material to synthesize the first [TismPriBenz] lanthanide complexes, [TismPriBenz]YbI and [TismPriBenz]YbCl₂. [TismPriBenz]YbI itself can further react with KN(SiMe₃)₂ and NaCp to give [TismPriBenz]YbN(SiMe₃)₂ and [TismPriBenz]YbCp respectively. Lastly, the ability of the [TismPriBenz]Zn halide series to form ion pair complexes was investigated. [TismPriBenz]ZnI can react with ZnI₂ to afford {[TismPriBenz]Zn}₂[Zn₃I₈], which contains the novel zinc halide species [Zn₃I₈]²⁻. Additionally, all of the [TismPriBenz]ZnX (X = Cl, Br, I) complexes are able to react with excess ZnX₂ in THF to give the series {[TismPriBenz]Zn}[Zn(THF)X₃].

No description available.