Addition of a Thallium Vertex to Empty and Centered Nine-Atom Deltahedral Zintl Ions of Germanium and Tin

A systematic approach to the formation of endohedrally filled atom clusters by a high-temperature route instead of the more frequent multistep syntheses in solution is presented. Zintl phases Na12Ni(1-x)Sn17 and K(13-x)Co(1-x)Sn17, containing endohedrally filled intermetalloid clusters [Ni@Sn9](4-) or [Co@Sn9](5-) beside [Sn4](4-), are obtained from high-temperature reactions. The arrangement of [Ni@Sn9](4-) or [Co@Sn9](5-) and [Sn4](4-) clusters, which are present in the ratio 1:2, can be regarded as a hierarchical replacement variant of the hexagonal Laves phase MgZn2 on the Mg and Zn positions, respectively. The alkali-metal positions are considered for the first time in the hierarchical relationship, which leads to a comprehensive topological parallel and a better understanding of the composition of these compounds. The positions of the alkali-metal atoms in the title compounds are related to the known inclusion of hydrogen atoms in the voids of Laves phases. The inclusion of Co atoms in the {Sn9} cages correlates strongly with the number of K vacancies in K(13-x)Co(1-x)Sn17 and K(5-x)Co(1-x)Sn9, and consequently, all compounds correspond to diamagnetic valence compounds. Owing to their diamagnetism, K(13-x)Co(1-x)Sn17, and K(5-x)Co(1-x)Sn9, as well as the d-block metal free binary compounds K12Sn17 and K4Sn9, were characterized for the first time by (119)Sn solid-state NMR spectroscopy.

Section: Resultssupporting

confidence: 58%

Endohedrally Filled [Ni@Sn₉]⁴⁻ and [Co@Sn₉]⁵⁻ Clusters in the Neat Solids Na₁₂Ni_1−xSn₁₇ and K_13−xCo_1−xSn₁₇: Crystal Structure and ¹¹⁹Sn Solid‐State NMR Spectroscopy

Hlukhyy

Stegmaier

Wüllen

et al. 2014

“…Reactions of transition‐metal, lanthanide, or even actinide organometallic reagents with homoatomic polyanions of Group 14, Group 15, and heteroatomic tetrahedral Group 14/15 or Group 13/15 anions provide a powerful route toward the synthesis of a variety of metal‐doped clusters. Selected examples represent ligand‐free monometallic doped clusters, such as [Ni@E 9 ] q − (E=Ge or Sn),, [Cu@E 9 ] 3− (E=Sn or Pb), [Ni@Pb 10 ] 2− , [M@Pb 12 ] x − (M=Ni, Pd, Pt, Mn, or Rh), [Ir@Sn 12 ] 3− , [U@Bi 12 ] 3− , and [Eu@Sn 6 Bi 8 ] 4− . So far, only a limited number of clusters with higher nuclearities ( n >14) involving more than one interstitial metal atom have been structurally characterized .…”

Section: Introductionmentioning

confidence: 99%

[Co₂@Ge₁₆]⁴⁻: Localized versus Delocalized Bonding in Two Isomeric Intermetalloid Clusters

Liu

Popov

et al. 2017

We report the successful isolation and structural elucidation of two bimetallic doped [Co @Ge ] clusters (α and β form), which were synthesized through the reaction of [{(ArN) CtBu}Co(η -toluene)] (Ar=2,6-diisopropylphenyl) and K Ge in ethylenediamine (en) solution and co-crystallized together in [K(2,2,2-crypt)] [Co @Ge ]⋅en. The α-[Co @Ge ] isomer prefers a distinct D 3-connected architecture, whereas the deltahedral isomeric β-[Co @Ge ] isomer adopts a quasi-C geometry and can be seen as coupling of two distorted arachno-[Co@Ge ] units. Chemical bonding analyses indicate that the skeleton of the α isomer is mainly composed of localized bonds, whereas only multicenter bonding interactions govern the geometry of the β isomer, which was further found to exhibit a fluxional behavior. The coexistence of both isomers within one unit cell links the 3-connected clusters with their deltahedral congeners, thus highlighting the structural and electronic flexibility of such discreet cluster systems.

“…[40] With as keletal electron number of 2n = 14, the quoted anion lacks two skeletal electrons and was therefore described as pre-closo cluster( additionally indicating the apparently high tolerance for different total electron counts in theseh eavy metal cluster anions). Therefore, the anion in 8 represents the first 7-atom closo clusterw ithin the Zintl anion family.T he most striking consequence of the two additional electrons for the structure is as ignificant elongation of the apical···apical interatomic distance from 3.4622 (9) in (Tl 7 ) 7À (in K 10 Tl 7 )t o 4.10 on average in (Tl 4 Bi 3 ) 3À (4.08 and 4.11 in the two symmetry-independentanions in 8).…”

Section: Solution Chemistry:binary Zintl Anionsmentioning

confidence: 99%

“…These were first characterizeds olely by NMRspectroscopy and later also crystallographically. [9] Our goal was to find as ynthetic access to new binary Zintl anions with group 13 elements,a iming for their furtheru se as synthetic buildingb locks for ternary intermetalloid clusters, as previously shown for (E 13 Bi 3 ) 2À (E 13 = Ga, In, Tl). In these anions, the high charge of the E 13 atoms is "diluted" by formally neutralB i atoms.…”

Section: Introductionmentioning

confidence: 99%

The Identity of “Ternary” A/Tl/Pb or K/Tl/Bi Solid Mixtures and Binary Zintl Anions Isolated From Their Solutions

Lichtenberger

Franzke

Massa

et al. 2018

Investigations of solid mixtures of the elemental combinations A/Tl/Pb (A=Na, K) and K/Tl/Bi indicate the presence of multiple binary and ternary Zintl phases, among them new ones containing Tl and Pb or Bi, respectively. Extractions with en/crypt-222 afford single crystals of several novel binary anions, including [Tl@Tl Pb ] and (Tl Bi ) . [Tl@Tl Pb ] adopts a closo-type cage structure despite possessing one additional electron; it is therefore isostructural, yet not isoelectronic, with homoatomic [Tl@Tl ] obtained by solid state reactions. (Tl Bi ) is a rare case of a pentagonal bipyramidal Zintl anion, yet the first binary one, and (unlike Tl ) the first one with a proper closo-type electron count. Assignment of the numbers and positions of the Tl/Pb or Tl/Bi atoms within the anionic clusters, indistinguishable in classical X-ray diffraction experiments, was achieved by means of quantum chemistry. The studies shed light on the complex situation in solid heavy element mixtures and their substantial differences from the composition of the Zintl anions obtained from them by extraction.