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The synthesis of a series of lanthanide trifluoroacetic acid (H-TFA) derivatives which contain only the TFA and its conjugate acid has been developed. From the reaction of Ln(N(SiMe3)2)3 with an excess amount of H-TFA, the products were identified as: [Ln(μ-TFA)3(H-TFA)2]n (Ln = Y, Ce, Sm, Eu, Gd, Tb, Dy), [Ln(μ-TFA)3(μ-H-TFA)]n·solv (Ln·solv = Pr·2 H-TFA, H3O+, Ho·2py, Er·py, Yb·py, H-TFA), 3[H][(TFA)La(μ-TFA)3La(TFA)(μ-TFA)2(μc-TFA)2]n ½(H2O) ½(H2O, H-TFA) (La·½(H2O) ½(H2O, H-TFA)), [(k2-TFA)Nd(μ-TFA)3]n·H-py+ (Nd·H-py+), [(py)2Tm(μ-TFA)3]n (Tm), or [Lu(μ-TFA)4Lu(μ-TFA)3·H3O+]n (Lu·H3O+). The majority of samples formed long chain polymers with 3 or 4 μ-TFA ligands. Tm was isolated with py coordinated to the metal, whereas Ho, Er, and Yb were isolated with py located within the lattice. Select samples from this set of compounds were used to generate nanomaterials under solvothermal (SOLVO) conditions using pyridine (py) or octylamine at 185 °C for 24 h. The SOLVO products were isolated as: (i) from py: La – fluocerite (LaF3, PDF 98-000-0214, R = 9.64%, 35(0) nm), Tb – terbium fluoride (TbF3, PDF 00-037-1487, R = 4.76%, 21(2) nm), Lu lutetium oxy fluoride (LuOF, PDF 00-052-0779, R = 8.24%, 8(2) nm); (ii) from octylamine: La – fluocerite/lanthanum oxide carbonate (LaF3, PDF 98-000-0214, R = 7.47%, 5(0) nm; La2O2(CO3), PDF 01-070-5539, R = 12.32%, 12(0) nm), Tb – terbium oxy fluoride (TbOF, PDF 00-008-0230, R = 7.01%, 5(0) nm); Lu – lutetium oxide (Lu2O3, PDF 00-012-0728, R = 6.52%, 6(1) nm).

A series of hydrated hexafluoro-iso-propoxide (hfip) lanthanide complexes was synthesized from the amide-alkoxide exchange reaction of the lanthanide bis-trimethylsilyl amide dissolved in toluene and an excess amount of H-hfip. The products were isolated and identified by single crystal X-ray diffraction as: [cis-(H2O)2(hfip)2Ln(μ-hfip)]2 (Ln = Ce, Pr, Nd, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y), [trans-(H2O)2(hfip)2Sc(μ-hfip)]2 (Sc), [(H2O)2(hfip)2La2(μ-hfip)3(μ3-OH)]2 (La-OH), and [(H2O)(hfip)2Sc(μ-hfip)(μ-OH)(μ3-OH)Sc(H2O)(hfip)]2 (Sc-OH). All species were found to have bound H2O molecules thought to be present in the hfip. For the non-oxo species, dinuclear species were formed with one bridging and two terminal hfip ligands. The waters were cis-oriented for all samples but the smallest derivative, Sc, where they were located in trans arrangement. Oxo species were formed by ‘aged’ hfip and generated tetranuclear species (La-OH and Sc-OH) that possessed different ligand sets. Initial efforts to determine these compounds utility for LnF3 nanomaterial production were undertaken using amine solvent in solvothermal (SOLVO) or solution precipitation (SPPT) routes. LnF3 phases were noted but often this was mixed with the Ln(O,F) or Ln2O3 phases.

This study investigates the use of a recently published generalized scaling law [J. Opt. Soc. Am. A 33(12), 2477-2484 (2016)]. In practice, the generalized scaling law accurately predicts the diffraction-limited peak irradiance in the far-field given the beam power, wavelength, propagation distance, field-effective area, and field-out-coupling factor. After reviewing this scaling-law formulation, we compare the far-zone predictions for peak irradiance and Gaussian beam spread to wave-optics simulations. Overall, the results show that this scaling-law formulation does not predict the correct peak irradiance, nor the correct Gaussian beam spread for horizontal-path scenarios with varying levels of atmospheric turbulence.