In the 2018 Nuclear Posture Review, it has been emphasized that the continued production of nuclear materials is and will continue to be an essential part of American interest and policy. Necessarily, the cleanup and environmental management of excess nuclear waste, especially from the Cold War era, also continues to be an ongoing effort. For example, just the disposition of legacy plutonium, amounting to 34 MT, is not scheduled to be complete for several decades. The electrochemistry of lanthanide and actinide ligand complexes has been studied to various degrees. In some cases, this area has been very understudied. Most of the known coordination complexes are unstudied. Plutonium as an element perhaps presents some of the most interesting redox phenomena, exhibiting up to four oxidation states simultaneously in solution. Later actinides berkelium and californium have very scarce published literature, especially non-aqueous based electrochemistry. Other physical data such as log β and diffusion coefficients are also hard to find for many actinides. The beginning chapters focus on a well-studied ligand, 2,6-pyridinedicarboxylic acid (H2DPA) that has been well-characterized in solid-state methods for the lanthanides and actinides. This ligand has almost exclusively been studied under aqueous conditions, yet for reductive efforts with elements such as Sm, developing a non-aqueous approach was preferred. Detailed solubility investigations are provided, as well as detailed studies with cerium and plutonium, and finally studies with europium and samarium. The next set of chapters deals with later actinide investigations. For reductive electrochemistry with californium, detailed studies with cryptand were developed with the lanthanides. A preferred method was developed that was ultimately used to obtain novel data for californium. In the case of Bk, a pyridyl nitroxide ligand (pyNO) was used to collect the first non-aqueous cyclic voltammogram for this element. Lastly, the final chapter covers a few others systems that were given some efforts. Many of these systems have very interesting electrochemistry, but they were beyond the scope of just one dissertation to complete. These include Schiff bases and DOPO chemistry. The Schiff base data adds insightful data along with the tetravalent chemistry studied in earlier chapters, while the DOPO chemistry covers non-innocent redox phenomena affected by Pu. / A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2018. / September 27, 2018. / Actinides, Berkelium, Californium, Cyclic Voltammetry, Electrochemistry, Lanthanides / Includes bibliographical references. / Thomas E. Albrecht-Schmitt, Professor Directing Dissertation; Todd Adams, University Representative; Yan-Yan Hu, Committee Member; Michael Shatruk, Committee Member.

Source: Dissertation Abstracts International, Volume: 31-09, Section: B, page: 5245. / Thesis (Ph.D.)--The Florida State University, 1970.

The nickel (II) complex of the macrocyclic ligand 7,16-dihydro-6,8,15,17-tetramethyldibenzo{b,i}{1,4,8,11}-tetraazacyclotetradecinato (abbreviated Ni TMTAA) undergoes an oxidative dimerization reaction at the 7,16-positions. The complexes of cobalt (III) and other early transition metals are stable to this reaction. In order to study the factors that govern the course of this reaction the characteristics of the oxidized species were investigated. To stabilize the ligand to the coupling reaction to allow spectroscopic observation of the oxidized complexes, the 7 and 16 positions were encumbered by attachment of benzoyl groups. The nickel (II) and cobalt (III) complexes of the disubstituted ligand were electrochemically oxidized and studied via ESR and visible spectroscopy. The oxidized nickel complex is characterized as a distinctive 6-coordinate Ni(III) species in strongly coordinating media. In weakly to moderately coordinating solvents the oxidized compound is 4 or 5 coordinate and is intermediate between a metal-based and a ligand-based radical. The oxidized cobalt compound is predominately a ligand-based radical with a ('59)Co hyperfine of only 13 G. A mechanism for the dimerizaton based on the inhibitory effects of axial ligands is offered to account for the large stability differences between the oxidized nickel and cobalt complexes of the unsubstituted ligand. / In a related study, the sensitivity of anodic redox processes of Ni TMTAA to substitution on the macrocyclic ligand was investigated. A number of complexes derived from three patterns of substitution were prepared. Nine previously unreported compounds have been synthesized. The E(, 1/2) values of the first oxidation wave were measured by cyclic voltammetry. The substitution sensitivities of this process were quantitated by the Hammett equation and expressed in terms of (rho) values. The (rho) values obtained are discussed and compared to similar studies with other tetraaza macrocyclic complexes including metalloporphyrins. / The synthetic methodology developed for the substituted Ni TMTAA complexes was exploited for the preparation of a "capped" macrocyclic ligand. The iron(II) complexes of such a ligand have potential applications to reversible oxygenation studies. The synthesis and prelimary characterization of the nickel(II) complex is reported. There are some indications that the isolated compound may be in fact a cofacial dimeric species rather than a monomer. / Source: Dissertation Abstracts International, Volume: 43-07, Section: B, page: 2204. / Thesis (Ph.D.)--The Florida State University, 1982.

Source: Dissertation Abstracts International, Volume: 40-09, Section: B, page: 4291. / Thesis (Ph.D.)--The Florida State University, 1979.

Source: Dissertation Abstracts International, Volume: 40-09, Section: B, page: 4293. / Thesis (Ph.D.)--The Florida State University, 1979.

Source: Dissertation Abstracts International, Volume: 40-09, Section: B, page: 4295. / Thesis (Ph.D.)--The Florida State University, 1979.

The rates of reduction of the dioxouranium(VI) ion by 4,4$\sp\prime$-dipropylsulfonate-2,2$\sp\prime$ bipyridinium radical anions (ZV$\sp-$ radicals) were determined in the presence of the synthetic polyelectrolytes polyvinylsulfate (PVS), polyacrylic acid (PAA), and polymaleic acid (PMA) using the pulse radiolysis technique. In aqueous PVS solutions the rates of reduction of U(VI) by ZV$\sp-$ radicals are interpreted to reflect territorial binding of U(VI) in the electrostatic field of PVS. In contrast to these results, rate data obtained in PAA and PMA solutions are consistent with the interpretation of site binding of a portion of U(VI) to the carboxylate groups. The specificity of U(VI) binding to PAA is suggested by kinetic experiments in which substitutionally - inert Ru(NH$\sb3$)$\sb6\sp{3+}$ is reduced by ZV$\sp-$ radicals in PAA solutions. Plausible mechanisms for these reactions are presented. / In addition, kinetic data for the reduction of the dioxoactinide(VI) ions, UO$\sb2\sp{2+}$, NpO$\sb2\sp{2+}$, and PuO$\sb2\sp{2+}$ by ZV$\sp-$ radicals were determined at pH 4.0. The measured rate parameters for the reduction of UO$\sb2\sp{2+}$ and NpO$\sb2\sp{2+}$ are in agreement with those predicted by Marcus theory for outer sphere electron transfer, after allowances are made for diffusion. / Source: Dissertation Abstracts International, Volume: 49-12, Section: B, page: 5300. / Major Professor: Gregory R. Choppin. / Thesis (Ph.D.)--The Florida State University, 1988.

The M(CO)$\sb{\rm 6-x}$(PF$\sb3$)$\sb{\rm x}$ complexes where M is Cr, Mo and W and x is 0 to 6 are known. The reactivity of both isomeric forms of the complexes x = 2 and 3 with $\sp{13}$CO and PF$\sb3$ were studied under purely thermal and under photolytic conditions. The results for the thermal reactions in which the samples were in the gas phase are: for chromium and tungsten (100 and 140$\sp\circ$C respectively) the complexes isomerize exclusively via an intramolecular process as there is no C-13 incorporation and only a steady state equilibrium is attained between the isomers. For the molybdenum complexes (100$\sp\circ$C), the reaction is principally an intermolecular process. When starting with either fac- or mer-Mo(PF$\sb3$)$\sb3$(CO)$\sb3$, the intermediate is rigid; stereoselective C-13 incorporation in the Mo(PF$\sb3$)$\sb2$($\sp{13}$CO)(CO)$\sb3$ produced is observed. When starting with either cis- or trans-Mo (PF$\sb3$)$\sb2$(CO)$\sb4$, it appears that the intermediate (Mo(PF$\sb3$)(CO)$\sb4$) will rearrange to place the vacancy cis to the phosphine. In condensed state thermal reactions, for molybdenum complexes, the products obtained result from $\sp{12}$CO and PF$\sb3$ release which remain trapped in the lattice and are reattached. The degree of C-13 incorporation is reduced due to small amount of sample that is volatilized and the small solubility of CO in the complexes at elevated temperatures. Photolytic reactions of the Cr, Mo and W complexes at 100$\sp\circ$C with $\sp{13}$CO present reveal a large degree of product scrambling. When the samples were photolyzed while dissolved in methylcyclohexane, the reaction speed was reduced but is primarily nonselective. Photolytic reactions either neat or in MeCH with PF$\sb3$ present, yielded highly substituted products (x $>$ 3). Finally, procedures to prepare the fac-Mo (PF$\sb3$)$\sb3$(CO)$\sb3$ / isomer in large relative yields are discussed. These reactions were studied with packed column gas chromatography and infrared spectroscopy. / Source: Dissertation Abstracts International, Volume: 51-04, Section: B, page: 1810. / Major Professor: Ronald J. Clark. / Thesis (Ph.D.)--The Florida State University, 1990.

The complexation of Np(V) with aliphatic (oxalic, malonic, succinic, glutaric, and maleic) and aromatic (phthalic, pyromellitic, hemimellitic, trimellitic, and mellitic) polycarboxylic acids was studied by spectrophotometry at 1 M ionic strength (NaClO$\sb4$) and 23$\sp\circ$C. For the aliphatic systems, the stability of the neptunyl complexes was found to decrease as the carbon chain length of the ligand increased which was attributed to an entropy effect. / In polycarboxylate systems, the stability constant decreased in the order hemimellitate $>$ mellitate $>$ pyromellitate $>$ trimellitate, phthalate. With the exception of hemimellitate, this trend follows the order of decreasing basicity of the ligand. After correction of the stability constant for statistical effects, the stability of the mellitate, pyromellitate, trimellitate, and phthalate complexes were approximately the same. / The unexpected strength of hemimellitate complexation was attributed to an increase in electron density at the binding site from the non-chelating carboxylate group through induction. / The complexation of phthalate, trimellitate and hemimellitate and mellitate were studied as a function of pH. Trimellitate and mellitate were found to form MHL as well as ML complexes while for phthalate and hemimellitate only ML species were observed. / The stability constants of the cation-cation complexes Np(V)-U(VI) and Np(V)-Np(V), measured at 6 M ionic strength (HClO$\sb4$) and 25$\sp\circ$C, were found to be 2.45 $\pm$ 0.05 and 1.41 $\pm$ 0.14, respectively. The change in enthalpy for the Np(V)-U(VI) system as determined by the measurement of the stability constant as function of temperature was $-$14.3 $\pm$ 1.6 kJ/mol. / Source: Dissertation Abstracts International, Volume: 50-07, Section: B, page: 2921. / Major Professor: Gregory R. Choppin. / Thesis (Ph.D.)--The Florida State University, 1989.

Substitution of CO with PF$\sb3$ in the Group VIIB dimetal decacarbonyls has been studied under thermal and photolytic conditions. Substitution via photolysis is faster and results in the production of a greater number of isomers. Under both thermal and photolytic conditions, a maximum of four CO ligands may be replaced with PF$\sb3$ in Mn$\sb2$(CO)$\sb{10}$. At least eight of the carbon monoxides can be replaced in Tc$\sb2$(CO)$\sb{10}$, whereas Re$\sb2$(CO)$\sb{10}$ can be fully substituted with PF$\sb3$. Under thermal conditions the rate of reaction proceeds Tc $\gg$ Re $>$ Mn at 130$\sp\circ$C, while under photolytic conditions Tc $\gg$ Mn $>$ Re. For Mn, the metal-metal bond strength does not vary within experimental error from the parent upon the substitution of a single CO with PF$\sb3$. The mixed-metal decacarbonyls, MnTc(CO)$\sb{10}$, MnRe(CO)$\sb{10}$, and ReTc(CO)$\sb{10}$ were synthesized and their reaction with PF$\sb3$ investigated. The possible mechanisms for substitution are reexamined, based upon the observed products. / Source: Dissertation Abstracts International, Volume: 49-07, Section: B, page: 2638. / Major Professor: Ronald J. Clark. / Thesis (Ph.D.)--The Florida State University, 1988.