Structural diversity of volatile mixed ligand complexes of alkaline earth element hexafluoroacetylacetonates with triglyme and related polyglymes

A One‐Pot Synthesis of “K(hfa) glyme” Adducts: Effect of the Polyether Length on the Ion Coordination Sphere

“…[18][19][20] Potassium ion has a large ionic radius (r 6-coord = 1.51 Å), [13] which is responsible for interesting coordination moieties giving rise, in function of the coordinating ligands to extended oligomeric or polymeric network. [21][22][23] Former studies have shown that glymes play a crucial role in stabilizing complexes of alkaline-earth, [24][25][26][27][28] transition [29,30] and rare-earth metals [31,32] through oxygen-ion complexation. Recently, we have also devoted our attention to alkali metals, namely Li [33] and Na.…”

Journey of a molecule from the solid to the gas phase and vice versa: direct estimation of vapor pressure of alkaline-earth metalorganic precursors for atmospheric pressure vapor phase deposition of fluoride films

“…As a result of the studies carried out by diverse research groups new monomeric, volatile, and thermally stable metal sources of the type M(β-diket) 2 •polyether for thin film deposition via MOCVD techniques have emerged. 18,19,[21][22][23][24][25][26][27][28][29] All the alkaline-earth metals forming the above-mentioned precursors, have a +2 oxidation state, but their coordination number tends to increase (Mg < Ca < Sr < Ba) with the increasing of the ionic radius. Nevertheless, there is essentially no preferential coordination geometry, at difference with transition metals, with the exception of a preferred spherical distribution of the donor atoms.…”

“…In particular, Tsymbarenko et al devoted their attention to study the structures, thermal stability and volatility of Ca, Sr, and Ba hexafluoroacetylacetonates mixed ligand complexes with various polyethers. 27 For these metal-organic adducts, the authors have investigated their volatility and thermal stability in the gas phase through mass spectrometry (MS) and density functional theory (DFT) calculations. 27 Starting from present thermogravimetric analyses, and as confirmed by the studies of Tsymbarenko et al 27 and Luo et al, 48 all the investigated compounds evaporate congruently.…”

“…and [Ca(hfa) 2 •tetraglyme]. 18,21,24,25,27 In the [Ca(hfa) 2 •diglyme• H 2 O], seven oxygen atoms from the two hfa anionic ligands and the diglyme ligand plus one oxygen from the water molecule complete the coordination spere of the central metal ion Regarding the [Ca(hfa) 2 •tetraglyme] structure, the Ca 2+ is octacoordinated by the four oxygens from the hfa units and four of the five oxygen atoms from the tetraglyme ligand. 25 The TGA/DTG plots for the Ca adducts with different glyme ligands are reported in Fig.…”

“…This journal is © The Royal Society of Chemistry 2022 ently. 27 Instead, the [Ba(hfa) 2 •tetraglyme] adduct (dark blue line) has a one-step 88% weight loss in the temperature range between 432-553 K. Fig. S8 † depicts the vapor pressure/temperature plots.…”