Crystal Structure of Triaqua(1,10-diaza-18-crown-6)chlorobarium Chloride

The crystal structure of triaqua(1,10-diaza-18-crown-6)chlorobarium chloride [Ba(DA18C6)Cl(H₂O)₃]⁺Cl^–(I) is studied by X-ray diffraction analysis: space group Pnma, a= 14.912, b= 13.590, c= 10.456 Å, Z= 4. Structure Iis solved by the direct method and refined by the full-matrix least-squares method in the anisotropic approximation: R= 0.079 for all 3194 measured independent reflections (CAD-4 diffractometer, MoK ). Crystal Iexists as complex guest–host cations and Cl^–anions connected via interionic hydrogen bonds. The cations and anions are located in the msymmetry plane. The Ba²⁺ion (coordination number 10) is in the cavity of the DA18C6 macrocycle and is coordinated by its six heteroatoms (2N + 4O) and also by the Cl^–anion and two O atoms of two water molecules from one side of the macrocycle and by the O atom of the third water molecule from another side. The DA18C6 ligand in Ihas the conformation of a crown with an approximate D _3d symmetry.     

Neptunium(V) Carbamide Complexes. The structure of [NpO2(HCOO){OC(NH2)2}3]

A new complex of Np(V) [NpO₂(HCOO){OC(NH₂)₂}₃] (I) was synthesized and its crystal structure was determined: a = 6.674(1) Å, b = 13.164(2) Å, c = 7.020(1) Å, = 101.35(1)°, space group P2₁, Z = 2, V = 604.7(2) ų, R = 0.048, wR(F ²) = 0.128. The structure consists of infinite chains of [NpO₂(HCOO){OC(NH₂)₂}₃]. The coordination polyhedron of the Np atom is a pentagonal bipyramid with the O atoms of three carbamide molecules and two formate ions in the equatorial plane. The absorption spectra were measured in IR and near-IR regions for compound I and for the [NpO₂Cl{OC(NH₂)₂}₄] complex, whose structure was reported in the previous publication.     

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).     

Crystal Structure of Diaqua(1,2-bis(2-(o-hydroxy-phenoxy)ethyloxy)ethane)(isothiocyanato)strontium Thiocyanate

The aqua complex of podand 1,2-bis(2-(o-hydroxyphenoxy)ethyloxy)ethane (L) with strontium thiocyanate of the composition [Sr(NCS)L(H₂O)₂]⁺ · SCN^– (I), was synthesized and studied by X-ray diffraction analysis: space group P 2₁/c, a = 17.730 Å, b = 8.558 Å, c = 18.169 Å, = 116.15°, Z = 4. The structure was solved by direct method and anisotropically refined by the full-matrix least-squares method to R = 0.039 for 4333 independent reflections (CAD4 autodiffractometer, MoK ). Structure I contains complex cation [Sr(NCS)L(H₂O)₂]⁺ of the host–guest type. The coordination polyhedron of Sr²⁺ cation (coordination number 9) is a distorted pentagonal bipyramid with four oxygen atoms at the benzene rings of the L podand and the oxygen atom of one water molecule in its base, the N atom of the SCN^– ligand at its single vertex, and with the remaining two O atoms of the L podand and O atom of another water molecule at a triple vertex. In a crystal, the complex cations and SCN^– anions are joined through the hydrogen bonds to form bulky layers parallel to the xy plane.     

Copper(II) Complexes with N-(3-Hydroximino-2-methylbutan-2-yl)methylamine (HL): Synthesis and Properties. Crystal and Molecular Structures of [Cu(HL)Cl2] and [Cu(HL)(H2O)2SO4]n

Paramagnetic copper(II) complexes with N-(3-hydroximino-2-methylbutan-2-yl)methylamine (HL), namely, Cu(HL)Cl₂(I), Cu(HL)(SO₄) · 2H₂O (II), and Cu(HL)(NO₃)₂(III), were obtained. The crystal structures of I and II were determined. The blue crystals of these compounds are monoclinic. For I(C₆H₁₄Cl₂CuN₂O): a = 8.820(1) Å, b = 6.511(1) Å, c = 18.255(2) Å, = 92.86(1)° V = 1047.0(2) ų, space group P2₁/c, _calcd = 1.679 g/cm³, Z = 4 for R ₁ = 0.0250; for II(C₆H₁₈CuN₂O₇S): a = 9.999(2) Å, b = 9.927(2) Å, c = 12.963(3) Å, = 106.37(3)°, V = 1234.5(4) ų, space group P2₁/c, _calcd = 1.753 g/cm³, Z = 4 for R ₁ = 0.0324. Crystals of I have a molecular structure. The Cu coordination polyhedron is a square bipyramid (2N + 2Cl + Cl + Cl) due to additional contacts with two Cl atoms from the neighboring molecules. Structure II is built from polymeric chains. The environment of the Cu atom is a distorted cis-octahedron (2N + 2O(H₂O) + 2O(SO₄)). Complexes I–IIIare characterized by IR and EPR spectroscopy.     

Synthesis and Crystal Structure of Diaqua(2.2.2-Cryptand)strontium Dichloride Trihydrate

Absract—Diaqua(2.2.2-Cryptand)strontium dichloride trihydrate [Sr(2.2.2-Crypt)(H₂O)₂]²⁺ · 2Cl^– · 3H₂O (I) was prepared and studied by X-ray diffraction. The triclinic structure of I (space group P , a = 9.152 Å, b = 10.140 Å, c = 15.219 Å, = 88.84°, = 88.19°, = 87.62°, Z = 2) was solved by the direct method and refined by full-matrix least-squares calculations in the anisotropic approximation to R = 0.050 for 4188 independent reflections (CAD4 automated diffractometer, CuK radiation). The structure contains the [Sr(2.2.2-Crypt)(H₂O)₂]²⁺ host–guest cation. The Sr²⁺ cation resides in the 2.2.2-cryptand cavity and is coordinated by all eight heteroatoms (6O + 2N) of the cryptand ligand and by two O atoms of water molecules. The Sr²⁺ coordination polyhedron (C.N. 10) is a highly distorted dibase-centered two-cap trigonal prism. The crystal structure of I contains a branched system of ion–ion (intermolecular) hydrogen bonds O(w)–H···Cl^–, which connect the complex cations, the Cl^– anions, and the crystal water molecules to form infinite thick layers parallel to the yz plane.     

Thiourea N- and S-Derivatives as Ligands: Synthesis and Crystal Structure of 4CuCl · 6All–NHCSNH2 and [(All–NH)2C–SC2H5]Cu2ClxBr3 – x (x = 0.765, All is Allyl)

Crystals of the compounds 4CuCl · 6CH₂=CH–CH₂–NHCSNH₂ (I) and [(CH₂=CH–CH₂–NH)₂C–SC₂H₅]Cu₂Cl _x Br_{3 – x} (x = 0.765) (II) were synthesized by the ac electrochemical method, and their crystal structures were determined (CuK and MoK radiation, 2575 and 1090 unique reflections with F 4(F), R = 0.050 and 0.028 for I and II, respectively). Complex I crystallizes in space group C2/c, a = 17.230(7) Å, b = 12.258(5) Å, c = 42.95(2) Å, = 97.48(4)°, V = 8994(7) ų, Z = 8. The structure of -complex II is described by space group P2₁/n, a = 10.633(5) Å, b = 9.280(5) Å, c = 16.024(4) Å, = 102.16(3)°, V = 1546(1) ų, Z = 4. Complex I is built from isolated units of the aforementioned composition; every allylthiourea molecule coordinates two metal atoms through the sulfur atom. The distorted tetrahedral surrounding of every Cu(I) atom involves three S atoms and one Cl atom. The N,N"-diallyl-S-ethylisotiouronium cation coordinates two copper atoms through the C=C bonds, 1.32(1) and 1.35(1)Å, uniting the cuprohalide chains in layers. The structure of complex II is very close to the structure of the previously studied -complex of diallylammonium [H⁺L]Cu₂Cl₃.     

The crystal structure of tetraphenylarsonium tricyanooxopyridine-2-carboxylatotungstate(IV) dihydrate

Summary The structure of (AsPh₄)₂[WO(CN)₃(Pic)] · 2H₂O has been determined from three dimensional x-ray data. The cell dimensions are:a=17.699(8),b=13.546(6),c= 13.590(6) Å, =117.39(8), = 71.54(7) and = 115.04(8)°, space group P¯1, Z = 2, The structure was solved from 5279 observed reflections. The anisotropic refinement converged to R = 0.060.The [WO(CN)₃(Pic)]^2–-ion is a distorted octahedron. The structure indicates that the aqua group in [WO(CN)₄(H₂O)]^2– was displaced by an oxygen atom of the carboxylate of 2-picolinate, while a cyanide ligand was substituted by the pyridine nitrogen atom. Themer-arrangement of the three cyanide ligands has two normaltrans W-C_av = 2.17(2) Å bond distances and a significant shorter W-C = 2.042(18) Å bond trans to the W-N [2.188(18) Å] bond. The W=O and W-O bond lengths are 1.676(9)Å and 2.171 Å, respectively.     

Structure of the neutral metal complex Pt(dddt)2

A neutral metal complex, [Pt(dddt)₂]° (1), has been obtained by oxidation of the [Pt(dddt)₂]^– anion with excess (Bu₄N)AuBr₄ in nitrobenzene. Crystallographic data for 1a=17.854(9) Å,b=18.409(9) Å,c=4.717(5) Å, =68.83(2)°, space group P2₁/n,Z=4,d _calc=2.55 g/cm³. In1 two independent centrosymmetric [Pt(dddt)₂]° molecules are packed in stacks that form layers parallel to the (110) plane. The molecules of1 in the layers have shortened S...S contacts 3.491(9) Å, and 3.594(10) Å. The average bond lengths Pt-S 2.242(7) Å, S-C 1.71(2) Å and C=C 1.40(3) Å, together with the square-planar coordination of Pt in PtS₄, suggest considerable conjugation in the metal cycles.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1207–1209, July, 1993.     

Reaction of trimethylaluminum with crown ethers. III. The synthesis and crystal structure of (12-crown-4)bis(trimethylaluminum)

The crown ether 12-crown-4 reacts with trimethylaluminum in toluene to form the complex [AlMe₃]₂[12-crown-4]. Attempts to utilize the remaining two oxygen atoms for coordination to AlMe₃ molecules were unsuccessful. The 21 complex crystallizes in the monoclinic space groupP2₁/n witha=11.342(7),b=12.941(4),c=6.973(6) Å, and =95.48(4)°. Refinement led to a finalR value of 0.047 for 925 observed reflections. The molecule resides on a crystallographic center of inversion, and as required by symmetry, the four oxygen atoms are planar. The Al–O bond is strong as revealed by the bond length of 1.977(3) Å. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82013 (9 pages).     

Uncommon Behavior of Copper(I) Tetrafluoroborate and Perchlorate in [Cu(DAF)(H2O)]BF4and [Cu(DAF)(ClO4)] π-Complexes (DAF—Diallyl Formamide)

Crystals of [Cu(DAF)(H₂O)]BF₄(I) and [Cu(DAF)(ClO₄)] (II) (DAF is diallyl formamide) were synthesized by an alternate-current electrochemical method, and their structures were determined (MoK radiation, 1247 and 859 independent reflections with I 2(I), R= 0.043 and 0.032 for Iand II, respectively). The complexes crystallize in space group P2₁/n, Z= 4. For I, a= 10.782(3) Å, b= 12.096(5) Å, c= 9.185(3) Å, = 103.62(3)°, and V= 1164.2(7) ų; for II, a= 10.064(3) Å, b= 10.753(6) Å, c= 10.002(3) Å, = 87.52(4)°, and V= 1081.4(8) ų. The copper atom in structures Iand IIcoordinates both C=C bonds in one DAF molecule and oxygen atom of the amide group of another DAF molecule, as well as an oxygen atom of H₂O (in I) or ClO₄(in II) in the axial position. The uncommon behavior of the anions in structures Iand IIis explained by their different values of Pierson hardness.     

Molecular encapsulation of transition metal complexes in cyclodextrins. Part 2. Synthesis and crystal structures of 2:1 adducts between α-cyclodextrin and metallocenium hexafluorophosphates [η5-C5H5)2M]PF6(M = Fe,Co, Rh)

The title metallocenium salts form crystalline 2:1 host:guest inclusion compounds with-cyclodextrin, [(⁵-C₅H₅)₂M]PF₆ · 2-CD · 8H₂O (1, M = Fe;2, M = Co;3, M = Rh). The X-ray crystal structures of1 and3, and the lattice constants, crystal system and space group of2 have been determined. Crystal data: triclinic, space groupP1 (No. 1),Z = 1;1,a = 13.865 (2) Å,b = 13.839 (2) Å,c = 15.520 (2) Å, = 91.43 (2)°, = 85.81 (2)°, = 120.22 (2)°, andR _F = 0.089 for 4257 observed MoK reflections [I > 3(I)];2,a = 13.810 (2) Å,b = 13.872 (2) Å,c = 15.560 (2) Å, = 93.99 (2)°, = 87.06 (2)°, = 120.04 (2)°;3,a = 13.756 (1) Å,b = 13.863 (1) Å,c = 15.561 (2) Å, =94.39 (1)°, = 86.92 (1)°, = 119.89 (1)°, andR _F = 0.061 for 11142 observed MoK reflections [I > 3(I)]. In the crystals of1 and3, two -cyclodextrin molecules are arranged head-to-head to form a dimer by means of intermolecular hydrogen bonding across the secondary hydroxyl faces of adjacent -CD monomers. The dimers are stacked along the crystallographicc axis to form a channel-type structure. The metallocenium cation is encapsulated within the cavity of the dimer, while the PF ₆ ^– anion is located outside the cavity, being centered between the primary hydroxyl faces of adjacent dimers. Eight water molecules of hydration per asymmetric unit reside in the spaces between the -CD columns. In view of the almost identical crystal data for2 a similar structure can be assumed for the cobaltocenium adduct.     

Aminosulfuric acid: An excellent guest for crown ether complexation. Crystal structure of the 1∶1∶1 molecular complex between aminosulfuric acid,water and 18,19-benzo-1, 16-diaza-4,7,10,13-tetraoxacycloeicosa-17,20-dione

The twenty-membered macrocycle, 18,19-benzo-1, 16-diaza-4,7,10,13-tetraoxacycloeicosa-17,20-dione, C₁₈H₂₆N₂O₆ (1), aminosulfuric acid and water form a stoichiometric 111 inclusion compound. The crystal structure of [1·NH ₃ ⁺ SO ₃ ^– ]·H₂O has been determined by X-ray crystallography. The crystal is monoclinic, space groupP2₁/c, a=7.967(1),b=13.447(3),c=20.779(4) Å, =90.20(2) Å;Z=4. The finalR-value is 0.0434 for 4638 unique reflections withI>2(I). The structure consists of the 11 molecular complexes between the crown host and aminosulfuric acid revealing hydrogen bonding with the ligand ether and carbonyl oxygen atoms. The complexes are united in the layer-like structure by NH...O host-guest and NH...O=CF _obs,F _calc, tables of anisotropic displacement parameters, and fractional atomic coordinates of hydrogen atoms.     

Crystal and Molecular Structures of (Dibenzo-18-Crown-6)(Nitrato-O,O")-Tetrahydrofuranpotassium, [K(DB18C6)(THF)(NO3)]

The (dibenzo-18-crown-6)(nitrato-O,O")tetrahydrofuranpotassium complex [K(DB18C6)(THF)(NO₃)] (I) was synthesized and studied using X-ray diffraction analysis. The crystals are orthorhombic: a= 9.608 Å, b= 9.926 Å, c= 27.234 Å, Z= 4, space group P2₁2₁2₁. The structure was solved by the direct method and refined by the least-squares method in the anisotropic approximation to R= 0.099 over all 2620 measured independent reflections (CAD4 automated diffractometer, MoK radiation). Complex Iin the crystal exists as individual host–guest molecules, the K⁺cation (CN 9) being located in the DB18C6 macrocycle cavity and being coordinated to its six oxygen atoms and to two oxygen atoms of the nitrato ligand on one side of the macrocycle and to the THF oxygen atoms on the other side. The DB18C6 molecule in Ihas a butterfly conformation with approximate C _2V symmetry.     

Copper(I) Complexes with N-Allylquinolinium Bromide [C9H7N(C3H5)]CuBr2 and [C9H7N(C3H5)]Cu2Br3: Synthesis and Crystal Structure

Crystals of [₉₇N(₃₅)]uBr₂ (IV) and [₉₇N(₃₅)][u₂Br₃] (V) were prepared by ac electrochemical synthesis from uBr₂, N-allylquinolinium bromide, on copper electrodes in the ethanol–benzene medium. X-ray diffraction study has shown that crystals IV and V are monoclinic: space group A2₁/a, a = 13.776(3) Å, b = 14.304(3) Å, c = 13.147(2) Å, = 107.90(1) Å, V = 2465(2) ų, Z = 8 for IV and space group P2₁/n, a = 13.881(2) Å, b = 15.446(2) Å, c = 7.111(1) Å, = 104.64(1)°, V = 1475.0(8) ų, Z = 4 for V. Structures IV and V are built of the N-allylquinolinium cations and different anions i.e., (CuBr₂) ^n- _n forming infinite chains in IV and peculiar {[Cu^I ₄Br₆]^2–} _n arranged in polymeric chains in V. In the latter case, two independent metal atoms have trigonal–pyramidal and trigonal–planar environments. In the structures of both compounds, the C=C bond of the allyl group is not involved in coordination with the Cu(I) atom.     

The crystal and molecular structure oftrans-Di(methylsulphito)bis-(triphenylphosphine)platinum(II)

Summary The crystal and molecular structure oftrans-di(methylsulphito)bis(triphenylphosphine)platinum(II), Pt(SO₃Me)₂ (PPh₃)₂, derived from the reaction of Pt(PPh₃)₂ (O₂) with SO₂ in MeOH and in the presence of sodium tetraphenylborate(III), has been determined from diffractometer data. The complex crystallizes in the space group P ¯1- (C_i ¹) with one molecule in a unit cell of dimensionsa = 9.744(2) Å,b = 10.062(3) Å,c = 11.153(2) Å; = 68.59(2)°, = 82.69(2)° and = 62.25(2)°. Leastsquares refinement has led to a value of the conventional R index (on F) of 0.031 for the 3308 reflections having F²>3(F₀ ²). The complex is a typical square-planar platinum(II) complex with the platinum atom lying on a crystallographically imposed centre of symmetry. The important structural parameters are Pt-P 2.369(1) Å, Pt-S 2.308(1) Å, and the oxygen atoms complete an approximate tetrahedron about the sulphur atoms with S-O 1.448(5) Å and S-O(Me) 1.620(5) Å.     

Synthesis,crystal structure and ferro-magnetic interaction of a binuclear copper(II) complex with the 1,4-dinitro-2,3,5,6-tetracarboxylatobenzenic anion as bridging ligand

A binuclear complex [Cu₂(DTB)(DMF)₄(H₂O)]·2DMF (DTB = 1,4-dinitro-2,3,5,6-tetracarboxylatobenzenic anion; DMF = N,N-dimethylformamide) has been synthesized and its crystal structure determined by X-ray crystallography. In the complex Cu ion is located in a distorted square pyramidal environment with two oxygen atoms O(1) and O(3) from two carboxylate groups, another two oxygen atoms O(7) and O(8) from terminal ligands of two DMF molecules, and a fifth coordinated oxygen atom O(9) from the terminal ligand of one H₂O molecule, in which the O(8) atom is situated in the apex of the pyramid. DTB as bridging ligand coordinates two Cu ions through its four carboxylate groups. The variable-temperature magnetic susceptibility of the complex was measured in the 5–300 K range. The magnetic coupling parameter is consistent with a ferromagnetic exchange between the two copper(II) centers and the data fit a binuclear magnetic exchange model based on the Hamiltonian operator ( = -2J₁₂, ₁ = ₂= 1/2), giving the ferromagnetic coupling parameter of 2J = 1.80 cm^{- 1}. This is the first example of a tetracarboxylatobenzenic bridging complex exhibiting ferromagnetic interaction.     

Palladium Clusters Pd4(SEt)4(OAc)4and Pd6(SEt)12: Structure and Properties

Palladium clusters Pd₄(SEt)₄(OAc)₄(I) and Pd₆(SEt)₁₂(II) were synthesized and studied. Their structure was determined by X-ray diffraction analysis. For I, a= 9.774(2) Å, b= 10.821(2) Å, c= 13.061(3) Å, = 92.88(3)°, V= 1379.6(5) ų, (calcd.) = 2.182 g/cm³, space group P2₁/n, Z= 4, N _ref= 1558, and R= 0.031; for II, a= 10.581(1) Å, b= 10.584(2) Å, c= 11.478(2) Å, = 101.62(1)°, = 104.95(1)°, = 106.74(1)°, V= 1135.2(4) ų, (calcd) = 2.007 g/cm³, space group P1, Z= 1, N _ref= 2828, and R= 0.022. In cluster I, four Pd atoms form a planar cycle. The neighboring palladium atoms are bound by two acetate or by two mercaptide bridges, the Pd···Pd distances being 3.036–3.195 Å. In cluster II, Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.083–3.127 Å. The neighboring palladium atoms are bound by two mercaptide bridges. The formation of analogous clusters in solution was confirmed by IR spectroscopy.     

New uranyl complex with imidazolidine-2-one [UO<Subscript>2</Subscript>(Imon)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)](ClO<Subscript>4</Subscript>)<Subscript>2</Subscript>: Structure and some properties

A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO₂(Imon)₄(H₂O)](ClO₄)₂ (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P2₁/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) ų, (calcd) = 2.117 g/cm³, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov.     

Crystal structure of a dimeric nickel(II) complex with 3-imidazoline nitroxide radical

The crystal structure of an unusual dimeric Ni(II) complex with 3-imidazoline nitroxide LH=C₉H₁₄N₂O₂ of the formula Ni₂(LH)₄ has been determined. The structure is molecular, space group P2₁/c, with a=12.150(3) Å, b=11.229(3) Å, c=15.780(4) Å, =101.59(3)^o, and d _calc =1.54 g/cm³, for Z=2; V=2109(1) ų, R=0.059. In the centrosymmetric dimer, the Ni...Ni distance is 3.254(2) Å; the coordination polyhedron of Ni is a square pyramid (the coordination number is 5) formed by the donor O and N atoms of LH ligands acting as the bidentate-cyclic and bidentate bridged-cyclic structures. The Ni–O and Ni–N distances are 1.989(7) and 2.032(8) Å, respectively (for the atoms forming the pyramid base), and 2.000(8) Å to the apical N atom. The Ni atom is displaced from the base to the apex of the pyramid by 0.35 Å. The interatomic distances and the bond angles in the ligands agree with those for the previously studied M(LR)₂ complexes. The distances between the Ni(II) ions and the O O atoms inside the Ni(LH)₂ fragments are 5.39(1) and 5.45(1) Å, the intermolecular Ni...O distances exceed 6 Å, and the O...O distances are as long as 4.73(1) Å.Institute of Inorgamic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Stukturnoi Khimii, Vol. 34, No. 3, pp. 80–85, May–June 1993.Translated by T. Yudanova