Alkali metal and ammonium fluoro(trifluoroacetato)metallates M′[M′′3(μ3-F)(CF3COO)6(CF3COOH)3], where M′ = Li, Na, K, NH4, Rb, or Cs and M′′ = Ni or Co. Synthesis and crystal structures

Bimetallic Trifluoroacetates as Single-Source Precursors for Alkali–Manganese Fluoroperovskites

“…Metal−oxygen and metal−fluorine distances given in Table 2 were selected using these threshold values; a similar remark applies to the corresponding coordination environments depicted in Figure 1i−o. Distances thus obtained are within the ranges reported in the literature for alkali-metal−organic compounds containing fluorinated ligands (for example: Na−F in (i) NaMg-(PFTB) 3 (thf) 3 2.542−2.891 Å, 17 (ii) NaOC(CF 3 )(CH 3 ) 2 2.635−3.726 Å, 44 (iii) NaY(hfac) 4 2.90 Å, 27 (iv) [Na-(triglyme) 2 ][Y 2 (TFA) 7 (THF) 2 ] 2.700 Å, 25 and (v) Na 4 (tfa) 4 (diglyme) 2.729−3.043 Å; 45 K−F in (i) KMg-(PFTB) 3 (thf)(toluene) 2.817−3.163 Å, 17 (ii) KH(tfa) 2 2.962 Å, 46 and (iii) KMn(hfa) 3 3.11−3.37 Å; 16 Rb−F in (i) RbH(tfa) 2 3.10−3.45 Å 47 and (ii) Rb[(CF 3 SO 2 )CH] 3.263− 3.438 Å; 48 Cs−F in (i) Cs[Ni 3 (μ 3 -F)(tfa) 6 (tfaH) 3 ] 3.203− 3.558 Å, 18 (ii) CsH(tfa) 2 3.30 Å, 46 and (iii) Cs(hfac) 3.255− 3.722 Å 49 ). Bond length threshold values utilized in this work are remarkably close to those employed by Plenio to systematically analyze the coordination chemistry of the CF unit in metal−organic compounds in the solid state.…”

“…Furthermore, the potential of both complexes as single-source precursors for the corresponding fluoroperovskites was demonstrated in the solid state (synthesis of bulk NaMnF 3 ) 15 and in the gas phase (chemical vapor deposition of KMnF 3 films) 16 but not in solution. Other bimetallic compositions encountered in our literature search include Na−Mg, 17 Na− Ba, 17 Na−Ni, 18 Na−Cu, 19,20 Na−Zr, 21 Na−Ln (Ln = Y, rare earth), 22−27 K−Mg, 17 K−Sr, 17 K−Ba, 17 K−Fe, 28 K−Cu, 29 K− Ln, 17,30 Rb−Ni, 18 Cs−Ni, 18 and Cs−Ln. 31 Similar to what was observed for bimetallic Na−Mn and K−Mn complexes, none of these were investigated as single-source precursors for the solution-phase synthesis of mixed-metal fluorides; Na−Ln fluorinated complexes are the only exception.…”

Electronic Structure of a Mixed-Metal Fluoride-Centered Triangle Complex: A Potential Qubit Component

“…30 Analytical data were obtained by the microanalytical service of the University of Manchester. 19 F NMR was carried out at the University of Manchester. Heat-capacity measurements were carried out at the Institute Nanoscience in Modena using a Quantum Design PPMS and were modeled using PHI.…”

“…Additionally, if the terminal ligands are sufficiently labile, then simple postsynthetic substitution reactions can allow for the generation of families of closely related compounds sharing the same core. In fact, the only aspect of these compounds that is not readily changed is the identity of the central μ 3 atom: Only two carboxylate triangular-bridged complexes are known where the μ 3 atom is not oxygen, namely, M[Ni II 3 (μ 3 -F)(O 2 CF 3 ) 6 (L) 3 ] and M[Co II 3 (μ 3 -F)(O 2 CF 3 ) 6 (L) 3 ] (M = alkali metal), both reported by Tereshchenko et al 18,19 Triangular-bridged complexes are of particular interest to magnetochemists for a number of reasons, including (i) the ability to study the effects of systematic chemical changes (e.g., in M or the carboxylate) on the exchange interactions within a rigid core structure; (ii) the fact that a triangle is the smallest discrete geometry in which important physical effects such as spin frustration can be studied, leading to studies of, for example, antisymmetric exchange effects; 17 and (iii) the utility of triangles as excellent precursors for the supramolecular synthesis of larger polymetallic clusters and frameworks. 15,20 Although the use of oxides/hydroxides as bridging ligands in such clusters is common, compounds utilizing the isoelectronic fluoride remain rare.…”

Br2F7− and Br3F10−: peculiar anions showing μ2- and μ3-bridging F-atoms

“…[2][3][4][5][6][7][8][9][10][11][12][13] The highly strained tri(m-F)-bridges between various elements 1 are scarce with only some examples in the literature. [2][3][4][5][6][7][8][9][10][11][12][13] Bridges among three atoms (m 3 -F) are even more rare; [14][15][16][17][18][19][20][21] however, m 4 -F 22,23 and even cage-like m 6 -F 22,24,25 coordination types are known. In the vast majority of these compounds the fluorine atom bridges either metal atoms (thus, forming homoor hetero (oligo-)nuclear complexes), or, more rarely, metal and nonmetal atoms.…”