New open framework in the structure of K3[Cu3FZn2(PO4)4]

K₃[Cu₃FZn₂(PO₄)₄] has been prepared by hydrothermal synthesis and the crystal structure was determined by single crystal X-ray analysis: space group C2/c, a = 37.824(8), b = 9.813(2), c = 16.679(3) Å, β = 92.70(3)°, wR₂ = 0.057, R = 0.0255. An open framework structure is built by [CuO₅] and [CuO₄F] square pyramids, [CuO₄] flattened tetrahedra, [ZnO₄] and [PO₄] tetrahedra with potassium ions in the channels.     

A New Cu, Al Fluoride Disilicate CuAl2F2(Si2O7) and its Relations to Topaz

CuAl₂F₂(Si₂O₇) has been prepared by hydrothermal synthesis and its crystal structure was determined by single crystal X‐ray diffraction: space group Pnma, a = 8.8697(9), b = 14.084(2), c = 4.7553(5) Å, wR₂ = 0.056, R = 0.022. Cu²⁺ shows elongated square pyramidal coordination. Edge‐ and corner‐sharing [AlO₄F₂] octahedra with fluorine atoms in cis position form layers parallel to the ac plane. Along b these layers are linked by Si₂O₇ groups to form a three‐dimensional framework [Al₂F₂(Si₂O₇]^2–. In addition, the [CuO₅] pyramides connect two Al octahedra of neighbouring layers. The crystal structure is discussed as a derivative from topaz structure. The modular (or polysomatic) approach is used for this purpose, and for modelling hypothetical related compounds.     

Ce2[SeO3]3 and Pr2[SeO3]3: Non‐Isostructural Oxoselenates(IV) of the Light Lanthanoids

The crystal structures of Ce₂[SeO₃]₃ and Pr₂[SeO₃]₃ have been refined from X‐ray single‐crystal diffraction data. The compounds were obtained using stoichiometric mixtures of CeO₂, SeO₂, Ce, and CeCl₃ (molar ratio 3:3:1:1) or Pr₆O₁₁, SeO₂, Pr, and PrCl₃ (molar ratio 3:27:1:2) heated in evacuated sealed silica tubes at 830 °C for one week. Ce₂[SeO₃]₃ crystallizes orthorhombically (space group: Pnma), with four formula units per unit cell of the dimensions a = 839.23(5) pm, b = 1421.12(9) pm, and c = 704.58(4) pm. Its structure contains only a single crystallographically unique Ce³⁺ cation in tenfold coordination with oxygen atoms arranged as single‐face bicapped square antiprism and two different trigonal pyramidal [SeO₃]^2? groups. The connectivity among the [CeO₁₀] polyhedra results in infinite sheets of face‐ and edge‐sharing units propagating normal to [001]. Pr₂[SeO₃]₃ is monoclinic (space group: P2₁/n) with twelve formula units per unit cell of the dimensions a = 1683.76(9) pm, b = 705.38(4) pm, c = 2167.19(12) pm, and β = 102.063(7)°. Its structure exhibits six crystallographically distinct Pr³⁺ cations in nine‐ and tenfold coordination with oxygen atoms forming distorted capped square antiprisms or prisms (CN = 9), bicapped square antiprisms and tetracapped trigonal prisms (CN = 10), respectively. The [PrO₉] and [PrO₁₀] polyhedra form double layers parallel to (111) by edge‐ or face‐sharing, which are linked by nine different [SeO₃]^2? groups to build up a three‐dimensional framework. In both compounds, the discrete [SeO₃]^2? anions (d(Se⁴⁺–O^2?) = 166–174 pm) show the typical Ψ¹‐tetrahedral shape owing to the non‐bonding “lone‐pair” electrons at the central selenium(IV) particles. Moreover, their stereochemical “lone‐pair” activity seems to flock together in large empty channels running along [010] in the orthorhombic Ce₂[SeO₃]₃ and along [101] in the monoclinic Pr₂[SeO₃]₃ structure, respectively.     

The Reduction of AuF3 in Super Acidic Solution

AuF₃ is reduced in superacidic HF/SbF₅ solutions giving three products. 1. Orange [Au₃F₈·2SbF₅]. It has a layered structure built up by square planar Au^IIF₄ and Au^IIIF₄ units: Crystal structure: space group P2₁/c, a = 9.049(2), b = 8.424(1), c = 9.645(1)Å, β = 115.08(1)°. 2. Black [Au₃F₇·3SbF₅] has a ribbon structure, similarly built up by square planar Au^IIF₄ and Au^IIIF₄ units: Crystal structure: space group Pc, a = 9.991(1), b = 10.728(1), c = 15.222(1)Å, β = 95.304(2)°. 3. Yellow green [(Au(HF)₂] (SbF₆)₂·2HF with square planar Au^IIF₄ units that are formed by two fluorine atoms of the anions and two HF molecules as complex ligands. Crystal structure: Space group P¯, a = 5.482(1), b = 5.848(1), c = 9.309(2)Å, α = 89.522(4), β = 85.635(4), γ = 87.509(4)°.     

Crystal Structure and Raman Spectroscopic Study of K5[CuO2][CO3]

Air and moisture sensitive K₅[CuO₂][CO₃] was prepared via the azide/nitrate route from stoichiometric mixtures of the precursors CuO, KN₃, KNO₃ and K₂CO₃. According to the single‐crystal X‐ray analysis of the crystal structure [P4/nbm, Z = 2, a = 7.4067(5), c = 8.8764(8) Å, R₁ = 0.053, 433 independent reflections] K₅[CuO₂][CO₃] represents an ordered superstructure of Na₅[NiO₂][CO₃]. The structure contains isolated [CuO₂]^3– dumbbells and CO₃^2– anions, with the latter not connected to the transition element. Raman spectroscopic measurements confirm the presence of CO₃^2– in the structure.     

Synthesis and X-Ray Structure of New Copper(II) Nitrates: Cu(NO3)2 · H2O and β-modification of Cu(NO3)2

Blue crystals of a Cu(NO₃)₂ · H₂O were synthesized by interaction of CuO with boiling 100% HNO₃. Stable β-Cu(NO₃)₂ modification was obtained by the sublimation of copper(II) nitrate in evacuated ampoule over the 150→100°C temperature gradient for 24 hr. According to X-Ray single crystal analysis Cu(NO₃)₂ · H₂O is monoclinic with a = 6.377(1), b = 8.548(1), c = 9.769(1) Å, β = 100.41(1)°, Z = 4, and space group P2₁/c. β-modification Cu(NO₃)₂ is orthorhombic with a = 14.161(5), b = 7.516(3), c = 12.886(2) Å, Z = 12, and space group Pbcn. In the both structures Cu atoms are square coordinated by 4 O atoms at the distances ranging from 1.92 to 2.02 Å. In each structure there are also additional Cu? O bonds with the distance of 2.33 or 2.35 Å and some weaker ones with the distances in the range of 2.65–2.72 Å. In the Cu(NO₃)₂ · H₂O structure the [CuO₄] squares are connected by the bridging NO₃ groups into zigzag chains, which are linked into layers by the longer Cu? O bonds. In the β-Cu(NO₃)₂ structure the [CuO₄] fragments of two types are joined by the bridging NO₃ groups in a three-dimensional framework. Some correlations were found between N? O distances and coordination functions of O atoms.     

Über Oxide des neuen Formeltyps A[T4O4]: Zur Kenntnis von KLi3GeO4, KLi3SiO4 und KLi3TiO4

On Oxides of the New Formula Type A[T₄O₄]: KLi₃SiO₄, KLi₃GeO₄, and KLi₃TiO₄ The crystal structure of KLi₃GeO₄ has been determined from single crystal x-ray diffraction data. The unit cell is triclinic, space group P1 , a = 10.278(2), b = 7.511(1), c = 5.849(1) Å, α = 100.32(2), β = 110.07(2), γ = 90.32(2)°; Z = 4, R = 0,086₇, R_w = 0,079₃. Cubes of the composition KO_8/2 form chains parallel to [11 1] and are interlinked by tetrahedrally coordinated Li⁺ and Ge⁴⁺. KLi₃SiO₄ and KLi₃TiO₄ are isotypic. Effective coordination numbers (ECoN) and the Madelung part of lattice energy (MAPLE) have been calculated.     

CoSm(SeO3)2Cl,CuGd(SeO3)2Cl,MnSm(SeO3)2Cl,CuGd2(SeO3)4 und CuSm2(SeO3)4: Übergangsmetallhaltige Selenite von Samarium und Gadolinum

CoSm(SeO₃)₂Cl, CuGd(SeO₃)₂Cl, MnSm(SeO₃)₂Cl, CuGd₂(SeO₃)₄ and CuSm₂(SeO₃)₄: Transition Metal containing Selenites of Samarium and Gadolinum The reaction of CoCl₂, Sm₂O₃, and SeO₂ in evacuated silica ampoules lead to blue single crystals of CoSm(SeO₃)₂Cl (triclinic, , Z = 4, a = 712.3(1), b = 889.5(2), c = 1216.2(2) pm, α = 72.25(1)°, β = 71.27(1)°, γ = 72.08(1)°, R_all = 0.0586). If MnCl₂ is used in the reaction light pink single crystals of MnSm(SeO₃)₂Cl (triclinic, , Z = 2, a = 700.8(2), b = 724.1(2), c = 803.4(2) pm, α = 86.90(3)°, β = 71.57(3)°, γ = 64.33(3)°, R_all = 0.0875) are obtained. Green single crystals of CuGd₂(SeO₃)₂Cl (triclinic, , Z = 4, a = 704.3(4), b = 909.6(4), c = 1201.0(7) pm, α = 70.84(4)°, β = 73.01(4)°, γ = 70.69(4)°, R_all = 0.0450) form analogously in the reaction of CuCl₂ and Gd₂O₃ with SeO₂. CoSm(SeO₃)₂Cl contains [CoO₄Cl₂] octahedra, which are connected via one edge and one vertex to infinite chains. The Mn²⁺ ions in MnSm(SeO₃)₂Cl are also octahedrally coordinated by four oxygen and two chlorine ligands. The linkage of the polyhedra to chains occurs exclusively via edges. Both, the cobalt and the manganese compound show the Sm³⁺ ions in eight and ninefold coordination of oxygen atoms and chloride ions. In CuGd(SeO₃)₂Cl the Cu²⁺ ions are coordinated by three oxygen atoms and one Cl^— ion in a distorted square planar manner. One further Cl^— and one further oxygen ligand complete the [CuO₃Cl] units yielding significantly elongated octahedra. The latter are again connected to chains via two common edges. For the Gd³⁺ ions coordination numbers of ?8 + 1”? and nine were found. Single crystals of the deep blue selenites CuM₂(SeO₃)₄ (M = Sm/Gd, monoclinic, P2₁/c, a = 1050.4(3)/1051.0(2), b = 696.6(2)/693.5(1), c = 822.5(2)/818.5(2) pm, β = 110.48(2)°/110.53(2)°, R_all = 0.0341/0.0531) can be obtained from reactions of the oxides Sm₂O₃ and Gd₂O₃, respectively, with CuO and SeO₂. The crystal structure contains square planar [CuO₄] groups and irregular [MO₉] polyhedra.     

Studies in the flexibility of macrocyclic ligands. Crystal and molecular structure of 2,13-dimethy1-3,6,9,12,18-pentaazabicyclo (12.3.1) octadeca-(18),14,16-triene-dichloroion (III) hexafluorophosphate

The crystal structure of the title compound [FeL²Cl₂] [PF₆] is reported. Crystals are monoclinic with a = 11.747(9), b = 16.051(11), c = 11.964(10)Å, β = 98.1(1)°, Z = 4, Spacegroup P2₁/n. 1173 independent reflections above background have been refined to R 0.09. The coordination geometry around the Fe(III) ion is pentagonal bipyramidal with the two chlorine atoms in axial positions [Fe-Cl 2.348(7), 2.354(7)Å]. The five donor nitrogen atoms of the macrocycle form a pentagonal girdle with lengths in the range 2.20(2)–2.25(2)Å. The macrocycle conformation is compared to that found in [CuL²]²⁺ and [CoL²Cl]²⁺ where the 5N donor set provides respectively trigonal bipyramidal and square pyramidal environments and also to that found in the comparable 7-coordinate [FeL¹(NCS)₂]⁺ where L¹ is the related pentaene.     

Ein neues Oxocuprat (I): K3[CuO2]

A New Oxocuprate(I): K₃[CuO₂] For the first time K₃[CuO₂] was prepared in transparent, dark yellow single crystals from KO_0.52 and Cu₂O (sealed Cu-cylinders, 660⁰C, 25 d). The crystal structure, P4₁2₁2, with a = 859.4(0), c = 1331.9(2) pm, Z = 8, dx = 2.85 g/cm₃, d_pyk = 2.84 g/cm³ was solved (four-circle-diffractometer data PW 1100, 1399 I₀(h k l), MoKα R = 0.068, Rw = 0.065). The crystal structure is characterized by isolated dumb-bell-like [O? Cu? O] units as well as by tedrahedron chains of the C. P. at 2/3 of the K⁺. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Einkristalle von Y3F[Si3O10] im Thalenit-Typ

Single Crystals of Y₃F[Si₃O₁₀] with Thalenite-Type Structure Colourless, diamond-shaped single crystals of Y₃F[Si₃O₁₀] (monoclinic, P2₁/n; a = 730.38(5), b = 1112.47(8), c = 1037.14(7) pm, β = 97.235(6)°, Z = 4) with thalenite-type structure are obtained upon the reaction of YF₃ with Y₂O₃ and SiO₂ (1 : 4 : 9 molar ratio) in evacuated silica tubes at 700 °C in the presence of CsCl as flux within seven days. The crystal structure consists of triangular [FY₃]⁸⁺ cations and catena-trisilicate anions [Si₃O₁₀]^8–, which exhibit a horseshoe-shape resulting from two vertex-shared terminal [SiO₄] tetrahedra with both staggered and eclipsed conformation relative to the central one. The Y³⁺ cations have coordination numbers of seven plus one (Y1) or seven (Y2 and Y3), but only one F^– anion belongs to each and vice versa, the remainder ligands being oxygen members of [Si₃O₁₀]^8– anions.     

Crystal Structure of the B‐type Dierbium Oxide ortho‐Oxosilicate Er2O[SiO4]

The crystal structure of B‐type Er₂O[SiO₄] has been determined by single crystal X‐ray diffraction. It crystallizes with the (Mn,Fe)₂[PO₄]F type structure in the monoclinic space group C2/c (a = 14.366(2), b = 6.6976(6), c = 10.3633(16) Å, ß = 122.219(10)°, Z = 8) and shows anionic tetrahedral [SiO₄]^4– units and non‐silicon‐bonded O^2– anions in distorted [OEr₄]¹⁰⁺ tetrahedra. The [(Er1)O₆₊₁] and [(Er2)O₆] polyhedra form infinite chains which are connected by common edges.     

Crystal structure and magnetic properties of Cu3(TeO3)2Br2—a layered compound with a new Cu(II) coordination polyhedron

The new compound Cu₃(TeO₃)₂Br₂ crystallizes in the monoclinic spacegroup C2/m. The unit cell parameters are a=9.3186(18)Å, b=6.2781(9)Å, c=8.1999(16)Å, β=107.39(2)°, Z=2. The structure is solved from single crystal data, R₁=0.021. The new compound shows a layered structure where only weak van der Waals interactions connect the layers. There are two crystallographically different Cu(II) atoms; one having a square planar [CuO₄] coordination and one showing an unusual [CuO₄Br] trigonal bi-pyramidal coordination, the Br-ion is located in the equatorial plane. The Te(IV) atom has a tetrahedral [TeO₃E] coordination where E is the 5s² lone-pair. Within the layers the Cu-polyhedra are connected by corner- and edge sharing to form chains. The chains are separated by the Te atoms. The magnetic properties are dominated by long range magnetic ordering at . Evidence for a coexistence of ferromagnetic and antiferromagnetic interactions exists.     

Oxocuprate(I) mit CO2-analogem Anion: Rb3[CuO2] [1]; (3. Mitteilung)

Inhaltsübersicht. Rb₃[CuO₂] wurde als dunkelgelbes Pulver bzw. erstmals in Form transparenter gelber, blockförmiger Einkristalle durch Tempern der binären Oxide (RbO_0,63/Cu₂O, Rb: Cu = 3,1:1 [Pulver] bzw. 4,2:1 [Einkristalle]) hergestellt (geschlossene Cu-Bömbchen, 600°C/10 d, bzw. 560°C/14 d, dann langsam abgekühlt). Nach Strukturaufklärung (a = 930,9(1); b = 966,8(2); c = 675,5(1) pm, β = 110,1(1)°, P2₁/n–C⁵_2h, Z = 4, Vierkreisdiffraktometer AED2, MoKα, 1409 von 1573 I_o(hkl), R = 14,6%, R_w = 10,0%) liegt ein neuer Strukturtyp vor (Parameter siehe Text). Strukturcharakteristisch sind die CO₂-analogen Hanteln [O–Cu–O] mit d(Cu–O) = 177 pm. Die Struktur wird beschrieben. Der Madelunganteil der Gitterenergie, MAPLE, effektive Koordinationszahlen, ECoN, diese über mittlere fiktive Ionenradien, MEFIR, werden berechnet und diskutiert. Oxocuprates(I) with CO₂-analogues Anions: Rb₃[CuO₂] (3^rd Communication) For the first time Rb₃[CuO₂] was prepared as dark yellow powder resp. yellow single crystals from the binary oxides (RbO_0.63/Cu₂O, Rb: Cu = 3.1:1 [powder] resp. 4.2:1 [single crystals], sealed Cu-cylinders). The crystal structure (a = 930.9(1); b = 966.8(2); c = 675.5(1) pm, β = 110.1(1)°, P2₁/n–C⁵_2h, Z = 4, four circle diffractometer AED2, 1409 out of 1573 I_o(hkl), R = 14.6%, R_w = 10.0%) was solved. The characteristic element is the CO₂-analogues group [O–Cu–O] with d(Cu–O) = 177 pm. The structure is described. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Synthese,Kristallstrukturen und spektroskopische Untersuchungen von 3d-Übergangsmetall-Komplexen mit Bicyclo[2.2.1]hept-5-en-2-endo,3-cis-dicarbonsäure und N,N-Donorliganden

Synthesis, Crystal Structures and Spectroscopic Investigations of 3d-Transition Metal Complexes with Bicyclo[2.2.1]hept-5-ene-2-endo,3-cis-dicarboxylic Acid and N,N-Donor Ligands The synthesis of coordination compounds of the general type [MLdam(H₂O)₃] · 2.5 H₂O with M = Mn²⁺, Co²⁺, Ni²⁺; H₂L = bicyclo[2.2.1]hept-5-ene-2-endo,3-cis-dicarboxylic acid and dam = 2,2′-dipyridyl, 1,10-phenanthroline has been described. The complexes have been characterized by elementary analysis, infrared and electronic spectra and magnetic susceptibility measurements. The results of X-ray crystal structure analyses of [MnLdipy(H₂O)₃] · 2.5 H₂O ( 1 a ) and [CoLdipy(H₂O)₃] · 2,5 H₂O ( 1 b ) show, that both compounds crystallize isotypically and prove the octahedral coordination of the metal atoms. The dicarboxylate anion is coordinated to the central atom by an O atom of only one carboxylate group, the other one is in the ionic state. One O atom of each carboxylate group makes an intramolecular hydrogen bond with a water molecule of the coordination sphere. The other crystal water molecules form a network of H bonds one with another and with the complex molecules, thus stabilizing the crystal packing.     

Bismuth(III) Complexes with N,N‐Di(2‐hydroxylethyl)aminodithiocarboxylate: Synthesis and Crystal Structure of {Bi[S2CN(C2H4OH)2]2[1, 10‐Phen]2(NO3)}·3H2O and (Bi[S2CN(C2H4OH)2]3}2

Two novel one‐ and two‐dimensional network structure bismuth(III) complexes with N, N‐di(2‐hydroxylethyl)‐aminodithiocarboxylate, {Bi[S₂CN(C₂H₄OH)₂]₂[1, 10‐Phen]₂(NO₃)}·3H₂O (1) and (Bi[S₂CN(C₂H₄OH)₂]₃)₂ (2) were synthesized. Their crystal and molecular structures were determined by X‐ray single crystal diffraction analysis. The crystal 1 belongs to monoclinic system with space group C2/c, a=1.6431(7) nm, b=2.4323(10) nm, c= 1.2646(5) nm, β=126. 237(5), Z=4, V=4.076(3) nm³, D_c=1.757 Mg/m^3, μ=4.598 mm^?1, F(000)=2156, R= 0.0211, wR=0.0369. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atom. The one‐dimensional chain structure was formed by H‐bonding interaction between hydroxyl group of N, N‐di(2‐hydroxylethyl)aminodithiocarboxylate ligands and crystal water. The crystal 2 belongs to monoclinic system with space group p2(1)/c, a= 1.1149(4) nm, b=2.1274(8) nrn, c=2.2107(8) nm, β=98.325(8)°, 2=4, V=5. 188(3) nm³, Dc=1.920 Mg/m³, μ=7.315 mm^?1, F(000)=2944, R=0.0565, wR=0.0772. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atoms. The two‐dimensional network structure was formed by H‐bonding interaction between adjacent molecules.     

A Novel 3‐D Heterobimetallic Cyano‐bridged Coordination Polymer Incorporating Ag···Ag Interaction: [Cu(dien)Ag(CN)2]2[Ag2(CN)3][Ag(CN)2]

A three‐dimensional cyano‐bridged copper(II) complex, [Cu(dien)Ag(CN)₂]₂[Ag₂(CN)₃][Ag(CN)₂] ( 1 ) (dien = diethylenetriamine), has been prepared and characterized by X‐ray crystallography. Complex 1 crystallized in the monoclinic space group P2₁/n with a = 6.988(2), b = 17.615(6), c = 12.564(4) Å, β = 90.790(5)°. The crystal consists of cis‐[Cu(dien)]²⁺ units bridged by [Ag(CN)₂]^— to form a zig‐zag chain. The Ag atoms of the free and bridging [Ag(CN)₂]^— link together to form additional infinite zig‐zag chains with short Ag···Ag distances. The presence of Ag···Ag interactions effectively increases the dimensionality from a 1‐D chain to a 3‐D coordination polymer.     

catena‐Poly[thorium(IV)‐tetrakis(μ2‐3‐carboxyadamantane‐1‐carboxylato)]: a quadruple helical strand driven by a synergy of coordination and hydrogen bonding

The title compound, [Th(C₁₂H₁₅O₄)₄]_n, is the first homoleptic thorium–carboxylate coordination polymer. It has a one‐dimensional structure supported by the bidentate bridging coordination of the singly charged 3‐carboxyadamantane‐1‐carboxylate (HADC⁻) anions. The metal ion is situated on a fourfold axis (site symmetry 4) and possesses a square‐antiprismatic ThO₈ coordination, including four bonds to anionic carboxylate groups [Th—O = 2.359 (2) Å] and four to neutral carboxyl groups [Th—O = 2.426 (2) Å], while a strong hydrogen bond between these two kinds of O‐atom donor [O...O = 2.494 (3) Å] affords planar pseudo‐chelated Th{CO₂...HO₂C} cycles. This combination of coordination and hydrogen bonding is responsible for the generation of quadruple helical strands of HADC⁻ ligands, which are wrapped around a linear chain of Th^IV ions [Th...Th = 7.5240 (4) Å] defining the helical axis.     

Benzeneselenolates of Mercury(II). Crystal and Molecular Structures of [Hg(SePh)2] and (Bu4N)[Hg(SePh)3]

The reaction of dibenzenediselenide, (SePh)₂, with mercury in refluxing xylene gives bis(benzeneselenolato)mercury(II), [Hg(SePh)₂], in a good yield. (ⁿBu₄N)[Hg(SePh)₃] is obtained by the reaction of [Hg(SePh)₂] with a solution of [SePh]^– and (ⁿBu₄N)Br in ethanol. The solid state structures of both compounds have been determined by X-ray diffraction. The mercury atom in [Hg(SePh)₂] (space group C2, a = 7.428(2), b = 5.670(1), c = 14.796(4) Å, β = 103.60(1)°) is linearly co-ordinated by two selenium atoms (Hg–Se = 2.471(2) Å, Se–Hg–Se = 178.0(3)°). Additional weak interactions between the metal and selenium atoms of neighbouring molecules (Hg…Se = 3.4–3.6 Å) associate the [Hg(SePh)₂] units to layers. The crystal structure of (ⁿBu₄N)[Hg(SePh)₃] (space group P2₁/c, a = 9.741(1), b = 17.334(1), c = 21.785(1) Å, β = 95.27(5)°) consists of discrete complex anions and (ⁿBu₄N)⁺ counter ions. The coordination geometry of mercury is distorted trigonal-planar with Hg–Se distances ranging between 2.5 and 2.6 Å.     

Zur Kristallstruktur von CuGeO3

The crystal structure of CuGeO₃ (D _2h ⁵ -Pbmm) has been redetermined by means of 3-dimensional Fourier syntheses. The structure is built up by [CuO₄]- and [GeO₃]-chains (Einereinfachkette). The interatomic distances are found to be: Ge?O: 1,76₉ (2x) and 1,72₄ (2x) Å; Cu?O: 1,94₂ (4x) and 2,76₆ (2x) Å.