Zur Kristallchemie der Triäthanolaminkomplexe

-Sn[(OC₂H₄)₂NC₂H₄OH]₂ crystallizes with space group Pccn and cell dimensionsa=16.35 (2),b=7.26 (1),c=12.82 (1) Å andZ=4. The structure was solved by the heavy atom technique (571 observed reflections, R₁=5.9%). Tin is octahedrally coordinated by four oxygen and two nitrogen atoms (Sn–O 2.01; 2.04 Å, Sn–N 2.33 Å) of the triethanolamine molecules. The complexes possess a crystallographic two-fold axis of rotation. They are linked by hydrogen bonds, thus forming infinite chains parallel to the twofold axis.

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Die Kristallstruktur von Tetrachloräthylencarbonat—Antimon(V)-chlorid,C2Cl4O2CO·SbCl5

Zusammenfassung Die Kristallstruktur des Adduktes Tetrachloräthylencarbonat—Antimon(V)-chlorid, C₂Cl₄O₂CO·SbCl₅ wurde mit Hilfe der Schweratom-Methode aus dreidimensionalen Röntgendaten bestimmt und nach der Methode der kleinsten Quadrate bis zu einemR-Wert von 13,1% verfeinert (Raumgruppe P2₁/n — Nr. 14;a=10,13,b=12,15 undc=12,55 Å, =108°40). Die Elementarzelle enthält 4 Moleküle C₂Cl₄O₂CO· SbCl₅. Das Antimonatom ist oktaedrisch von 5 Chloratomen und dem Carbonylsauerstoffatom des Tetrachloräthylencarbonats umgeben (Sb–Cl 2,28–2,33 und Sb–O 2,40 Å).

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The crystal structure of tetrachloroethylene carbonate antimony(V) chloride, C₂Cl₄O₂CO·SbCl₅

The crystal structure of the adduct tetrachloroethylene carbonate antimony(V)-chloride, C₂Cl₄O₂CO·SbCl₅, has been determined by the heavy-atom method from three-dimensional X-ray data. The refinement of the parameters was carried out by least-squares resulting anR-value of 13.1% (space group P2₁/n — No. 14;a=10.13,b=12.15 andc=12.55 Å, =108°40). The unit cell contains 4 discrete molecules C₂Cl₄O₂CO·SbCl₅. The antimony atom is coordinated octahedrally by 5 chlorine atoms and the carbonyl oxygen atom of tetrachloroethylene carbonate (Sb–Cl 2.28–2.33 and Sb–O 2.40 Å).

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Die Kristallstruktur von Li4SiO4

Zusammenfassung Die Kristallstruktur des Lithiumorthosilicats wurde mittels dreidimensionaler Fourier-Synthesen und nach der Methode der kleinsten Quadrate bestimmt. Die Gitterparameter der monoklinen Elementarzelle (C _2h ² –P2₁/m) betragen:a=5,14;b=6,10;c=5,30 Å und =90,5°. Die Struktur enthält isolierte [SiO₄]-Tetraeder, welche durch [LiO _n ]-Polyeder (n=4, 5, 6) verknüpft sind. Hervorzuheben ist, daß sämtliche Lithiumlagen nur partiell besetzt sind. Als mittlerer Si–O-Abstand wurde 1,632 Å erhalten; als Mittelwerte der Li–O-Abstände für die verschiedenen Koordinationszahlen ergeben sich: 1,975 [4]; 2,099 [5] und 2,247 [6] Å.

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The crystal structure of lithium orthosilicate has been determined by means of three-dimensional Fourier syntheses and the least squares method. The lattice parameters of the monoclinic unit cell (P2₁/m–C _2h ² ) are:a=5.14;b=6.10;c=5.30 Å and =90.5°. The crystal structure contains isolated [SiO₄]-tetrahedra being connected by [LiO _n ]-polyhedra (n=4, 5, 6). The positions of the lithium atoms are partially occupied only. The average interatomic Si–O distance is found to be 1.632 Å. The averaged values for Li–O distances given for the different coordination numbers are: 1.975 [4]; 2.099 [5] and 2.247 [6] Å.

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Die Kristallstruktur des Lithium-enneagermanats Li4[Ge9O20]

The crystal structure of lithium enneagermanate, Li₄[Ge₉O₂₀], has been determined and refined by least-squares, using three-dimensional single-crystal data. The compounds crystallizes with monoclinic symmetry (a=12.43,b=8.00,c=7.49 Å, =91.0^o; C2–C₂ ³) building up a framework structure which exhibits some similarity with the structures of Li₂[Ge₄O₉] and Li₂[Ge₇O₁₅]. Out of the 18 Ge-atoms in the unit cell 14 are surrounded tetrahedrally by oxygen showing an average distance of 1.757 Å; the remaining 4 Ge-atoms are octahedrally coordinated with an average distance of 1.886 Å.

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Die Kristallstruktur des Lithium-enneagermanats Li₄[Ge₉O₂₀]

Zusammenfassung Die Kristallstruktur von Lithium-enneagermanat Li₄[Ge₉O₂₀] wird an Hand dreidimensionaler Einkristalldaten ermittelt und nach der Methode der kleinsten Quadrate verfeinert (R=0,083). Die monoklin kristallisierende Verbindung (a=12,43;b=8,00;c=7,49 Å; =91,0^o; C2–C₂ ³) besitzt eine Gerüstruktur, die einen ähnlichen Aufbau wie Li₂[Ge₄O₉] und Li₂[Ge₇O₁₅] zeigt. Von den 18 Ge-Atomen in der Elementarzelle liegen 14 in tetraedrischer Koordination mit einem mittleren Ge–O-Abstand von 1,757 Å vor; 4 Ge-Atome sind oktaedrisch umgeben, mit einem mittleren Ge–O-Abstand von 1, 1886 Å.

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Herrn Professor Dr.O. Hromatka zum 65. Geburtstag gewidmet.     

Die Kristallstruktur der Tieftemperaturmodifikation von Ag8GeS6

The low temperature form of Ag₈GeS₆ (synthetic argyrodite) is orthorhombic, space group Pna2₁, witha=15.149 (1),b=7.476 (2),c=10.589 (1), andZ=4. The crystal structure has been determined from 2-circle diffractometer data by means of direct methods and refined toR=0.081 for 3431 intensities. The structure consists of slightly distorted isolated GeS₄ tetrahedra (mean Ge–S bond length 2.212 Å) and two further sulphur atoms without bonds to the germanium atoms. The GeS₄ tetrahedra and the S atoms are connected by the Ag atoms to form a three-dimensional framework. Three types of Ag coordination by S atoms are encountered. Three Ag positions have a strongly distorted tetrahedral environment, four Ag positions an approximately planar threefold coordination, while one Ag atom is almost linearly coordinated by two S atoms. The Ag–S distances are 2.56–2.94 Å, 2.49–2.76 Å, and 2.42–2.44 Å, resp. All Ag atoms have at least one near Ag neighbour between 2.93 and 3.11 Å.

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Kristallstruktur von Trisilber(I)amidosulfat-3-Ammoniak-2-Wasser,Ag3SO3N · 3NH3 · 2H2O

An X-ray crystal structure analysis of colourless Ag₃SO₃N · 3NH₃ · 2H₂O was carried out at room temperature:M=504.79, orthorhombic, P2₁2₁2₁,a=6.275 (1) Å,b=11.826 (2) Å,c=14.299 (12) Å,V=1061.10 ų,Z=4,d _x=3.160 Mgm^–3,F(000)=940, Mo K, =0.71069 Å (graphite monochromator), =5.60 mm^–1,R=4.71%,R _w=4.96% (982 reflections, 120 parameters). The structure consists of Ag ribbons; each Ag atom is linearly co-ordinated to two N atoms with distances corresponding to covalent Ag-N bonds; no Ag-O coordination is observed; the N atom of the SO₃N group is surrounded by three Ag atoms; compared to amidosulfuric acid, the SO₃N group shows significant deformation.

     

Kristallstruktur von Trisilber(I)amidosulfat Monohydrat,Ag3SO3N · H2O

An X-ray crystal structure analysis of yellow Ag₃SO₃N · H₂O was carried out at room temperature:M=435.69, monoclinic, P2₁/n,a=11.628 (5) Å,b=8.058 (4) Å,c=12.034 (5) Å, =86.49 (3)°,V=1125.5 ų,Z=8,d _x =5.142 Mgm^–3, MoK, =0.71069 Å (graphite monochromator), =10.5 mm^–1,R=5.44%,R _w =5.85% (877 reflections, 118 parameters). The structure contains Ag planes with Ag-Ag distances shorter than in metallic silver. The nitrogen atoms of the SO₃N anion are covalently bonded to 4Ag atoms of these Ag planes, thus assuming the extraordinary coordination number of 5. The five crystallographically independent Ag atoms forming the Ag planes have approximate linear N-Ag-N coordination. In addition, the structure contains two Ag atoms which are ionically coordinated to 4 resp. 5O atoms of SO₃N and water. The colour-structure correlation of Ag(I) compounds with colourless anions is discussed.

Herrn Prof. Dr. mult.V. Gutmann zum 65. Geburtstag gewidmet.     

Zur Stereochemie des Te(IV) gegenüber Sauerstoff

Zusammenfassung Die Koordination von Sauerstoff um Te(IV) zeigt in Kristallstrukturen eine Besonderheit, welche bisher nicht erkannt worden zu sein scheint: Während die Konfiguration von Te(IV) mit seinen drei nächsten Nachbarn in Bindungslängen und Bindungswinkeln recht konstant ist, variiert die Länge der viertnächsten Te–O-Bindung stark (von 2.08 bis 2.98 Å); dennoch ist ihre Richtung bemerkenswert konstant, wenn man Te–O-Abstände größer als 2.75 Å vernachlässigt. Auch die Richtungen zu weiteren Sauerstoff-Nachbarn (bis 3.0 Å) sind nicht statistisch verteilt, sondern gewisse räumliche Bereiche werden vermieden. Es wird versucht, diese phänomenologischen Befunde zu interpretieren.

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Contributions to the stereochemistry of Te(IV) towards oxygen

In crystal structures, the coordination of oxygen around Te(IV) shows a peculiarity which does not seem to have been recognized by now: While the configuration of Te(IV) with its three nearest neighbours is relatively constant as to bond lengths and bond angles, the length of the forth Te–O-bond varies greatly (from 2.08 to 2.98 Å); its direction, however, is remarkably constant if one excludes Te–O-distances larger than 2.75 Å. Also the directions to additional oxygen neighbours (up to 3.0 Å) are not at random, but some directions in space are avoided. It is attempted to interpret the phenomena.

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Verfeinerung der Kristallstruktur von Kupfer(II)-hydroxichlorid,Cu(OH)Cl

The crystal structure of Cu(OH)Cl [a=5.555 (2) Å,b=6.671 (4) Å,c=6.127 (2) Å, =114.88 (3)°, space group P2_I/a,Z=4] was refined for 810 observed reflections with sin /0.80 Å^–1 toR=0.035. Crystals were synthesized under hydrothermal conditions. The copper atom is planar four coordinated by three oxygen atoms and one chlorine atom; two further chlorine atoms complete its coordination. The copper polyhedra share edges to build up sheets, which are connected by hydrogen bonds to the chlorine atoms of adjacent sheets.

     

Die Kristallstruktur von Li2GeO3

Zusammenfassung Die Kristallstruktur von Li₂GeO₃ wird mit Hilfe dreidimensionalerFourier-Synthesen und nach der Methode der kleinsten Quadrate bestimmt. Li₂GeO₃ ist isotyp mit Li₂SiO₃ und enthält [GeO₃]^2–-Ketten (Zweiereinfachkette). Die Gitterparameter der rhombischen Elementarzelle (C _2v ¹² –Cmc2₁) betragen:a=9,63₀,b=5,46₅ undc=4,85₀ Å. Als mittlere interatomare Abstände wurden erhalten: Ge–O=1,74 und Li–O=2,01 Å.

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The crystal structure of Li₂GeO₃ has been determined by means of 3-dimensional Fourier syntheses and least-squares method. Li₂GeO₃ is isostructural with Li₂SiO₃, containing [GeO₃]^2–-chains (Zweiereinfachkette). The lattice parameters of the orthorhombic cell (C _2v ¹² –Cmc2₁) are:a=9,63₀;b=5,46₅ andc=4,85₀ Å. The average interatomic distances are found to be: Ge–O=1,74 and Li–O=2,01 Å.

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Verfeinerung der Kristallstruktur des Natriummetagermanats,Na2GeO3

Zusammenfassung Die Kristallstruktur des Natriummetagermanats, Na₂GeO₃, wurde mit dreidimensionalen Daten bis zu einemR-Wert von 4.4% verfeinert. Daraus ergab sich für die Metagermanatkette ein mittlerer Ge–O-Abstand von 1.836 Å für das Brückensauerstoffatom und von 1.713 Å für das terminale Sauerstoffatom. Der mittlere Na–O-Abstand beträgt 2.39 Å (KZ=5).

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Refinement of the crystal structure of sodium metagermanate, Na₂GeO₃

The crystal structure of sodium metagermanate, Na₂GeO₃, has been refined by three-dimensional data resulting anR-value of 4.4%. The mean Ge–O distances in the metagermanate chain were found to be 1.836 Å for the bridging oxygen atom and 1.713 Å for the terminal oxygen atom. An average value of 2.39 Å was calculated for the Na–O distance (c.n.=5).

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Die Kristallstruktur der Verbindung Cd2Ge7O16

The crystal structure of Cd₂Ge₇O₁₆ has been determined by means of three-dimensional single-crystal data. A finalR-value of 6.3% was obtained by least squares refinement based on 230 observed reflexions. The tetragonal unit cell with the lattice parametersa=11.31 andc=4.63 Å contains two formula units Cd₂Ge₇O₁₆. The compound is built up by [GeO₄]-tetrahedra and [GeO₆]-octahedra forming a three-dimensional framework with the Cd atoms located in the cavities. The average interatomic distances are found to be: Ge–O=1.74 (tetrahedra), 1.89 (octahedra) and Cd–O=2.36 Å.

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Crystal structure of the Ni(II) complex with the nitroxyl radical derivative of 3-imidazoline and 1-butanol

The crystal structure was found for the Ni(II) complex with the nitroxyl radical derivative of 3-imidazoline L=C₁₀H₁₃N₂O₂F₃ and 1-butanol C₄H₉OH with the formula NiL₂(n-C₄H₉OH)₂ (a=10.907(2), b=16.769(5), c=12.321(3) Å, =96.33(2), =120.36(1), =106.3(2)^o, V = 1780.7(7) ų, d_calc=1.32 g/cm³, space group P1, Z=2, R=0.072). The structure was molecular in nature. Octahedral coordination of the nickel ion was found with the oxygen and nitrogen atoms of two bidentate L in the equatorial plane [Ni–O, 2.13 Å (av.); Ni–N, 1.99 Å (av.)] and the oxygen atoms [Ni–O_OH, 2.13 Å (av.)] of the OH groups of the alcohol molecules in the axial positions. The rather strong hydrogen bonds between the coordinated OH groups of the alcohol and oxygen atoms of the groups of the adjacent complex molecules (O...O, 2.78–2.84 Å) delineate layers, in which the distances between the paramagnetic sites of adjacent molecules Ni... are shorter than the intramolecular distances and much shorter than the analogous distances between adjacent layers. On the whole, this structure is similar to those of analogous compexes with other alcohols previously studied.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 2, pp. 119–125, March–April, 1993.     

Die Kristallstruktur von B(OC2H4)3N

Zusammenfassung B(OC₂H₄)₃N kristallisiert in der Raumgruppe P ca2₁ mit den Gitterkonstantena=11,46,b=6,62,c=9,79 Å undZ=4. Die Struktur konnte mit direkten Methoden und mit sukzessivenFouriersynthesen aufgeklärt werden [570 F(hkl), R=9,8%]. Bor befindet sich in tetraedrischer Umgebung von Sauerstoff (B–O 1,431, 1,432, 1,475 Å) und Stickstoff (B–N 1,693 Å). In der Struktur bestehen zwischen den Komplexen keine Wasserstoffbrücken.

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The crystal structure ofB(OC ₂H₄)₃ N. Triethanolamine complexes, IV

B(OC₂H₄)₃N crystallizes in space group P ca2₁ with cell dimensionsa=11.46,b=6.62,c=9.79 Å andZ=4. The structure has been solved by direct methods and byFourier syntheses [570 F(hkl), R=9.8%]. Boron is tetrahedrally surrounded by oxygen (B–O 1.431, 1.432, 1.475 Å) and nitrogen atoms (B–N 1.693 Å). In the structure no hydrogen bonds exist between the complexes.

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Reaction of early transition metal complexes with macrocycles. II. Synthesis and structure of TiCl3(H2O) · 18-crown-6, a compound with a unique bidentate bonding mode for the 18-crown-6 molecule

18-crown-6 reacts with TiCl₃ in CH₂Cl₂ to form a complex in which the crown ether functions as a tridentate ligand. Addition of moist hexane affords a molecular complex in which the crown ether functions as a bidentate ligand. A water molecule is bonded directly to the titanium atom and is further hydrogen bonded to three of the oxygen atoms of the crown. The deep blue crystals of the CH₂Cl₂ adduct belong to the monoclinic space groupP2₁/n witha=13.481(8),b=8.021(5),c=21.425(9) Å, =97.32(5)°, and _calc = 1.51 g cm^–3 forZ=4. Refinement led to a conventionalR value of 0.040 based on 873 observed reflections. The Ti–O bond distances for the crown oxygen atoms are 2.123(8) and 2.154(9) Å, while the oxygen atom of the water molecule is bonded at 2.072(8) Å. The octahedral coordination sphere of the titanium atom is completed by the three chlorine atoms at distances of 2.340(5), 2.352(4), and 2.373(4) Å. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82034 (10 pages).     

Synthesis,crystal structure and magnetic properties of triaquahexakis(μ2-betaine)(μ3-oxo)triiron(III) perchlorate heptahydrate

The synthesis and characterization of the oxo-centered carboxylato-bridged trinuclear iron(III) complex, triaquahexakis(₂-betaine)(₃-oxo)triiron(III) perchlorate heptahydrate are described. X-ray crystallography shows that the Fe^III atom in the complex has a slightly distorted octahedral geometry, coordinated by four oxygen atoms from different betaine ligands [Fe—;O = 2.009(3) 2.034(3) Å], one aqua ligand [Fe—O = 2.028(4) and 2.031(3) Å] and the central ₃-oxo atom [Fe—O = 1.917(2) and 1.917(3) Å]. The central oxygen is ideally coplanar with the plane of the three metal atoms. Magnetic susceptibility data (4–320 K) show the presence of an antiferromagnetic exchange interaction with a coupling constant of J = –20.2 cm^–1.     

Molecular structures of benzoylbenzo-12-crown-4 and diphenylacetylbenzo-12-crown-4 and possible reasons for different conformational states of their macrocycles

The molecular structures of (benzoyl)benzo-12-crown-4 (a=22.387,b=4.503,c=16.167 Å,d _calc=1.34 g cm^–3,Z=4, space groupP2₁ nc, DAR-UM, Cu-K,R=0.056) and (diphenylacetyl)benzo-12-crown-4 (a=8.866,b=23.337,c=10.737 Å;d _calc=1.25 g cm^–3,Z=4, space groupP2₁2₁2₁, DAR-UM, Cu-K, R=0.056) have been investigated. The differences in the conformations of the macrocycles and the degree of conjugation between the benzene ring orbitals and the lone pairs on the adjacent oxygen atoms in the macrocycle are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1906–1911, November, 1993.     

Crystal structure of synthetic Cu3SeO4(OH)4

Summary The crystal structure of synthetic Cu₃SeO₄(OH)₄ was determined by single crystal X-ray methods:a=8.382 (2) Å,b=6.087 (1) Å,c=12.285 (2) Å,V=626.8 ų,Z=4, space group Pnma,R=0.026,R _w =0.021 for 1255 independent reflections (sin / 0.8 Å^–1). The crystal structure is isotypic to that of the mineral antlerite, Cu₃SO₄(OH)₄. The copper atoms are Jahn-Teller distorted with Cu^[4+2]O₆ polyhedra forming triple chains along [010]. These chains are linked via SeO₄ tetrahedra and weak hydrogen bonds to a framework structure.

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Die Kristallstruktur von synthetischem Cu₃SeO₄(OH)₄

Zusammenfassung Die Kristallstruktur von synthetischem Cu₃SeO₄(OH)₄ wurde mittels Einkristall-Röntgenmethoden ermittelt:a=8.382 (2) Å,b=6.087 (1) Å,c=12.285 (2) Å,V=626.8 ų,Z=4, Raumgruppe Pnma,R=0.026,R _w =0.021 für 1255 unabhängige Reflexe (sin / 0.8 Å^–1). Die Kristallstruktur ist isotyp mit der des Minerals Antlerit, Cu₃SO₄(OH)₄. Die Kupferatome sind Jahn-Teller-verzerrt, die Cu^[4+2]O₆ Polyeder bilden Dreierketten entlang [010]. Diese Ketten sind über SeO₄-Tetraeder und schwache Wasserstoffbrücken zu einer Gerüststruktur verbunden.

     

Die Kristallstruktur von Ge5O[PO4]6

Zusammenfassung Die Kristallstruktur der Verbindung Ge₅O[PO₄]₆ wurde auf Grund dreidimensionaler Einkristalldaten ausWeissenberg-Aufnahmen ermittelt und nach der Methode der kleinsten Quadrate verfeinert: Raumgruppe ;a=7,994±0,004 undc=24,87±0,01 Å;Z=3; 467 unabhängige Reflexe;R=0,086.Die Kristallstruktur wird aus singulären [GeO₆]-Oktaedern und [Ge₂O₇]-Doppeltetraedern aufgebaut, die über [PO₄]-Tetraeder zu einem dreidimensionalen Strukturverband vernetzt sind. Die mittleren Abstände betragen: Ge^[6]–O=1,863, Ge^[4]–O=1,704 und P–O=1,525 Å.

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The crystal structure of Ge₅O[PO₄]₆

The crystal structure of Ge₅O[PO₄]₆ has been determined and refined by least-squares, using three-dimensional x-ray data fromWeissenberg-photographs: space group ;a=7.994±0.004 andc=24.87±0.01 Å;Z=3; 467 independent reflections;R=0.086.The crystal structure consists of isolated [GeO₆] octahedra and [Ge₂O₇] double tetrahedra which are linked by [PO₄] groups forming a three-dimensional network. The average interatomic distances are: Ge^[6]–O=1.863, Ge^[4]–O=1.704 and P–O=1.525 Å.

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Crystal Structure of Calcium [Aqua(Nitrilotriacetatocobaltate(II)] Tetrahydrate,Ca[Co(Nta)(H2O)]2· 4H2O

Crystals of Ca[Co^II(Nta)]₂· 6H₂O (I), where Nta^3–is a nitrilotriacetate ion, were synthesized and studied using X-ray diffraction analysis. They were found to be monoclinic: a= 6.991(1), b= 10.031(1), c= 16.238(3) Å, = 98.50(1)°, V= 1126.2(3) ų, space group P2₁/n, Z= 2, R ₁= 0.0241, wR ₂= 0.0636, GOOF = 1.050 (for 3132 reflections with I> 2(I)). Structure Iis composed of {[Co(Nta)(H₂O)]^–}₁anion chains united by Ca²⁺cations into a three-dimensional framework. The coordination polyhedra of Co and Ca atoms are distorted octahedra. The Co(II) atom environment includes atoms N(1), O(1), O(3), and O(5) of one Nta^3–ligand, a carbonyl O(2)" atom of the neighboring anion fragment, and an O(w1) atom of the water molecule. The shortest bond is formed by the Co atom with the bridging O(2)" atom in trans-position relative to atom N(1). The Co–O(2)" distance (2.029 Å) is noticeably shorter than the other bond lengths, Co–O(Nta) (2.069–2.103 Å), Co–O(w1), and Co–N(1) (2.155 and 2.177 Å, respectively). Cations Ca²⁺are located in the inversion centers and involve in their coordination atoms O(4), O(6), O(w2), and the oxygen atoms symmetrically bond to them and arranged at 2.271(1), 2.420(1), and 2.351(2) Å, respectively. The structural formula of the title compound is {Ca(H₂O)₂[Co(Nta)(H₂O)]₂}₃· 2H₂O.