Trigonal prismatic vs octahedral coordination geometry: syntheses and structural characterization of hexakis(arylthiolato) zirconate complexes

Treating [Li(tmeda)]2[Zr(CH3)6] with aryl thiols, HSC6H4-4-R, in a 1:6 stoichiometry in diethyl ether affords excellent yields of [Li(tmeda)]2[Zr(SC6H4-4-R)6], where R = CH3 (1(2-)) or OCH3 (2(2-)) and tmeda denotes N,N,N',N'-tetramethylethylenediamine. These complexes are air-sensitive canary-yellow solids, soluble in hexane, diethyl ether, THF, and acetonitrile, that form yellow single crystals of [Li(tmeda)](2)1 (diethyl ether solution) or [Li(THF)3](2)2 (THF solution) from saturated solutions at -20 degrees C. Both complexes were characterized by X-ray crystallography and consist of a zirconium atom coordinated solely by the sulfur atoms of six aryl thiolate ligands in a nonoctahedral geometry. In each structure the lithium cation coordinates to the three sulfur atoms on the triangular faces of the S6 pseudotrigonal prism. These lithium-sulfur interactions appear to play a role in determining the coordination geometry about the metal center by orienting the sulfur lone pairs of electrons slightly out of the plane defined by the S3 triangular face and tilted away from the zirconium atoms. A likely consequence is the positioning of the sulfur lone pairs of electrons away from orthogonality with the zirconium-sulfur vector, and hence, they are poorly arranged to pi-interact with zirconium. Complex 1(2-) with a twist angle of ca. 9.18 degrees (trigonal prism, 0 degree; octahedron, 60 degrees) agrees with the interpretations of computational studies on d degree complexes, which suggest that a nearly trigonal prismatic geometry is favored when the interaction between metal and ligand is primarily through sigma-bonds. The intrinsically weak pi-donor thiolate ligand is probably converted to a primarily sigma-bonding system by the lithium-sulfur interaction. On the other hand complex 2(2-) with a twist angle of ca. 30.38 degrees is trigonally twisted to the midpoint of the trigonal prismatic-to-octahedral reaction coordinate. In complex 2(2-) the 4-OCH3 group is an electron donor by resonance effects that possibly may lead to the movement away from the expected trigonal prismatic geometry due to either pi-interactions or electrostatics repulsion.     

A novel three‐dimensional heterometallic coordination polymer: poly[[diaquadi‐μ3‐chlorido‐μ2‐chlorido‐tri‐μ3‐nicotinato‐tricopper(I)gadolinium(III)] hemihydrate]

In the title polymeric heterometallic compound, {[Cu₃Gd(C₆H₄NO₂)₃Cl₃(H₂O)₂]·0.5H₂O}_n, comprising copper(I) and gadolinium(III) cations bridged by nicotinate (nic) ligands and chloride anions, the Gd^III centers display a bicapped trigonal prismatic geometry, defined by six carboxylate O atoms and two water molecules. For copper(I), one Cu center is three‐coordinated by three chloride ions and displays a trigonal–planar geometry; the other two Cu centers are four‐coordinated and display a very distorted tetrahedral geometry. The chloride anions act in μ₂‐ and μ₃‐bridging modes, linking the Cu^I ions into an infinite chain. The nic ligand exhibits a tridentate coordination mode, with the carboxylate O atoms linking to two Gd^III ions and the N atom linking to one Cu^I ion. Thus, a novel three‐dimensional heterometallic coordination polymer is constructed from Gd–carboxylate subunits and Cu—Cl chains. In addition, intra‐ and intermolecular O—H...O and O—H...Cl hydrogen bonds are also observed within the three‐dimensional structure. Topologically, the framework represents an unusual 3,6‐connected (4.8²)₃(4¹⁰.6⁵) net.     

Synthesis and Crystal Structure of a Two-dimensional Polymeric Holmium Complex〔Ho(H_2saln)_(1.5)(NO_3)_3〕

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Synthesis and Crystal Structure of a Novel Tetranuclear Zinc（Ⅱ） Coordination Polymer [Zn4（o-bda）4（p-pbim）4]n

A novel tetranuclear zinc（H） coordination polymer [Zn4（o-bda）a（p-pbim）4]n 1 （p-pbim = 4-pyridylbenzimidazole, o-bda2 = o-phenylenediacetic acid dianion） has been synthesized by a hydrothermal method and characterized by elemental analysis, IR and X-ray singlecrystal diffraction. The title complex crystallizes in monoclinic, space group of P21/n with α = 14.231（1）, b = 16.257（1）, c = 16.794（1） ]k, β = 100.26（1）°, V = 3823.1（2）A3, Z = 8, Dc = 1.573 g/cm^3,β = 1.321 mm^-1, F（000） = 1856, R = 0.0420 and wR = 0.111. The Zn（1） atom assumes a distorted trigonal bipyramidal geometry, involving three carboxyl O atoms from two different o-bda ligands and two N atoms from two p-pbim ligands. The Zn（2） atom is coordinated by two oxygens from two distinct bda2- anions and two nitrogen atoms from two p-pbim ligands to form a distorted tetrahedral geometry. The Zn（Ⅱ） atoms are alternately interlinked by o-bda ligands in bis-monodentate or chelating-bidentate and monodentate modes into one-dimensional undulate chains along axis c with the adjacent Zn…Zn distances of 8.32 and 8.47 A. Such neighboring chains are further extended into a 1D bi-chain structure with two different subrings A and B, which are 32- and 14-membered rings through interchain p-pbim ligands. There exists a 2D supramolecular network linked by intermolecular hydrogen-bonding interactions between the uncoordinated carboxylate 0（4） atom or coordinated carboxylate 0（7） atom and the uncoordinated imidazolyl N（2） and N（5） atoms with the O...N distances to be 2.695 and 2.807A.     

Ho(III)希夫碱大环配合物的合成、晶体结构及对DNA的切割活性

本文合成一个新的希夫碱大环配体硝酸Ho(III)配合物 [Ho(H2L)(NO3)2](NO3) (H2L表示大环配体Fig. 1),并进行了系统的物理表征. 晶体结构研究表明: 配合物晶体结构属六方晶系,P 3(1)21空间群,晶胞参数a=1.47213(7) nm,c=2.8998(3) nm,α=90°,γ=120°,V=5.4424(7) nm 3,Z=6,R＝0.0331, wR＝0.0928。中心离子Ho3+位于隔室大环配体的一侧并于希夫碱大环上的两个酚基氧原子和三个氮原子配位,两个双齿配位硝酸根分别从希夫碱大环平面的两侧与中心离子配位使中心离子形成扭曲的九配位三冠三棱柱配位构型。并通过凝胶电泳实验初步研究了该配合物对pBR322质粒DNA的切割作用。     

Synthesis and Structure of K[Cd(O2N‐C6H4‐NNN‐C6H4‐NO2)3], an Anionic 1, 3‐Bis(4‐nitrophenyl)triazenido Complex of Cadmium

The reaction of cadmium acetate in methanol with 1, 3‐bis(4‐nitrophenyl)triazene in THF in the presence of KOH yields K[Cd(O₂NC₆H₄NNNC₆H₄NO₂)₃] in form of hexagonal prismatic, red crystals with the trigonal space group R3¯ and a = 12.229(2), c = 48.988(10) Å and Z = 6. In the anionic cadmium complexes, which are located along the threefold axis, the Cd atoms are coordinated in a trigonal prismatic arrangement by the atoms N(1) and N(3) of three triazenido ligands. The potassium cations are coordinated icosahedrally by oxygen atoms of each one nitro group of six neighbouring anionic complexes. The Cd‐N distances are 2.376(4) and 2.350(4) Å, and the K‐O distances are in the range of 2.833(6) to 3.365(6) Å.     

Ternary chalcogenide compounds AB2X4: The crystal structures of SiPb2S4 and SiPb2Se4

The crystal structures of SiPb₂S₄ and SiPb₂Se₄ were determined from three dimensional X-ray diffraction data collected with Mo radiation. Both structures are monoclinic with space group $\text{P2}{}_1\text{c}$ and 4 formula units per unit cell. Lattice dimensions for SiPb₂S₄ are a = 6.4721(5) Å, b = 6.6344(9) Å, c = 16.832(1) Å, and β = 108.805(7)°. For SiPb₂Se₄, a = 8.5670(2) Å, b = 7.0745(3) Å, c = 13.6160(3) Å, and β = 108.355(3)°. The Si is tetrahedrally coordinated to S and Se with SiS about 2.10 Å and SiSe about 2.27 Å. The structural framework can be described as consisting of trigonal prisms of S or Se atoms which form a prismatic tube by sharing the triangular faces. These tubes in turn share edges to form corrugated sheets, with the unshared edges projecting alternately on each side of the sheet. The structures are very similar but not identical. In the sulfide one Pb is in sevenfold coordination and the other crystallographically independent Pb is in eightfold coordination. The PbS distances range from 2.82–3.50 Å. In SiPb₂Se₄ both Pb atoms are in sevenfold coordination. PbSe distances range from 2.97 to 3.54 Å. In the sulfide the Pb atoms form a zig-zag chain within the channels formed by the prismatic tubes while in the selenide they are in a straight line.     

Structural diversity within analogous compounds: syntheses and studies of M(SCH2CH2NH2)Cl (M = Zn, Cd, Hg)

The novel complexes [Zn(L)Cl] (1), [Cd(L)Cl] (2), [Hg(L)Cl] (3), {[Hg(L)Cl].NaOH.2H2O} (3.NaOH.2H2O), and {[Hg3(HL)2Cl6].2H2O} (4) (L = -SCH2CH2NH2) were prepared and investigated by means of IR spectroscopy and single-crystal X-ray diffraction. The crystal structures of 1, 2, and 3.NaOH.2H2O show chelating N,S-coordination of the cysteaminate ligand, bridging S, and terminally coordinating Cl. Apart from these common features, the coordination geometries and modes of intermolecular association are different. 1 forms a cyclic tetramer with a Zn4S4 ring, and 3.NaOH.2H2O contains one-dimensional [Hg(L)Cl]n chains with S-bridged Hg atoms. Zn and Hg atoms in 1 and 3.NaOH.2H2O are tetracoordinate with a distorted tetrahedral M(ClNS2) geometry (M = Zn, Hg). Each Cd atom of 2 binds to three S atoms and vice versa, such that layers of distorted Cd3S3 hexagons are formed. 2 is the first example for a compound exhibiting a group 12-group 16 layer structure, which can be described as an analogue of a graphite layer. Additionally, each Cd atom binds to a chlorine atom and a nitrogen atom from a cysteaminate ligand resulting in pentacoordination with a distorted trigonal bipyramidal Cd(ClNS3) geometry. 4 contains two differently coordinate Hg atoms. One displays a distorted trans-octahedral Hg(Cl4S2) geometry, while the other is coordinated by four Cl atoms and one S atom and additionally forms a long Hg...Cl contact.     

SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF IN-COMPLETE CUBANE CLUSTER C(MoCu_3S_3) (O)(μ-dtp)(PPh_3)_3]

<正> A new mixed-metal sulfido incomplete cubane cluster [(MoCuS3) (O) (μ-dtp) (PPh3)3] Cdtp = S2P (OC2H5)2] has been prepared by reaction of (NH4)2MoOS3 with Cu(dtp) (PPh3)2 in dimethylformamide solution. It crystallizes in the triclinic space group P1, a = 13.810(5), b = 19. 753(5), c=11. 719(4) A. α=99. 42(2), β=107. 24(3),γ=88. 05(3)°, V = 3012(2)A3, Dc = l. 51g/cm3and Z = 2. Final R=0. 046, Rw = 0. 056 for 7700 unique intensity data(I≥3σ(I)). The central unit [MoCu3S3]3+ can be described as a distorted incomplete cube with one missing corner. The Mo atom is tetrahedrally coordinated by three μ3-S atoms and one terminal O atom. Two Cu atoms are tetrahedrally coordinated whereas the third Cu atom has a highly distorted trigonal environment. The mean Mo - Cu bond length is 2. 752A. The Cu...Cu distances are in the range of 3. 200(1) -3. 740(1) A which are too long to form bonds.     

Eine neue Modifikation von Lanthanmonosilicid – lT-LaSi

A New Modification of Lanthanum Monosilicide – lT-LaSi La metal and silicon react at 950 °C in the presence of LaBr₃ to form LaSi with the hitherto unknown low temperature modification (lT-LaSi). lT-LaSi crystallizes in Cmcm with a = 456.21(2), b = 1348.03(5), c = 662.59(6) pm. The Si atoms are connected to form cis-trans-cis-trans chains with alternating distances of d_Si–Si = 248 and 260 pm. They are coordinated in a trigonal prismatic fashion by the La atoms. lT-LaSi shows metallic conductivity.     

Interlocking inorganic screw helices: synthesis,structure, and magnetism of the novel framework uranium orthothiophoshates A11U7(PS4)13 (A = K,Rb)

The novel quaternary uranium thiophosphate K11U7(PS4)13 has been synthesized by reacting uranium metal, K2S, S, and P2S5 at 700 degrees C in an evacuated silica tube. The crystal structure was determined by single crystal X-ray diffraction techniques. K11U7(PS4)13 crystallizes in the tetragonal space group I42d (a = 32.048(2) A, c = 17.321(1) A, Z = 8). The structure contains a tunnel framework composed of eight interlocking uranium U7(PS4)13 screw helices, with alkali metal cations residing inside the framework channels. The uranium atoms are coordinated in a bi- or tricapped trigonal prismatic fashion. The screw helices are built up from uranium atoms interconnected by PS4 tetrahedral units. Magnetic susceptibility measurements indicate modified Curie-Weiss-type behavior between 300 and 70 K, with an effective magnetic moment of 2.54 microB per U atom at room temperature and C = 3.78, theta = -14.54, chi 0 = 0.01. The isostructural compound Rb11U7(PS4)13 (a = 32.1641(11) A, c = 17.7244(9) A, Z = 8) was prepared by heating a mixture of the formal composition UPS5 in eutectic LiCl/RbCl melts at 700 degrees C.     

Synthesis and Structure of K_6PMo_7V_2W_3O_(40)(H_2O)_(16)

1INTRODUCTIONHeteropolycompoundsareacidsaswellasoxidizingagents"'.Takingadvantageoftheseproperties,heteropolycompoundshavebeenusedascatalystsforvarioussyntheticreaction(bothinhomogeneousandheterogeneoussystems).Hydrationofpropeneinaliquidphasecatalyzedbyheteropolyacidshasbecomeacommercializedprocess.Oxidationofmethacroleinorisobutyricacidtoproducemethacrylicacidisanexampleofindustrialprocessestowhichthesecompoundsareapplied"--'>.Theoxidationpotential(oroxidizingability)decreaseslinearlywi…     

[ZnN(CH2CH2NH2)2(CH2CH2N=CHC6H4O)]·Pic的合成与晶体结构

在不加任何碱的条件下,三[2-(亚水杨基胺)乙基]胺与苦味酸锌[Zn(Pic)26H2O]在乙醇中反应,得到了较为少见的多胺单缩合西夫碱配体的配合物[ZnN(CH2CH2NH2)2(CH2CH2N=CH-C6H4O)]Pic。化学式为C19H23N7O8Zn,Mr=542.81,晶体属三斜晶系,空间群为P,晶胞参数为a=0.7494(3),b=1.1917(5),c=1.3142(6)nm,a=78.111(7),b=79.093(7),g=78.577(7),V=1.1121(8)nm3,Dc=1.621g/cm3,m(MoKa)=1.167mm-1,Z=2,F(000)=560,在1.602s(I)的可观测点为2433个,最终偏离因子R=0.0555,wR=0.1139。配合物中Zn(II)与配体的4个N原子和1个O原子配位形成变形的三角双锥结构,桥头N和O为锥顶,4个配位N中桥头N与金属离子的配位作用最弱。晶体通过p-p堆积和分子内、分子间的氢键作用形成二维层状超分子结构。     

Synthesis and Crystal Structure of Fe（aapo）2Cl3 （aapo=2—Acetylamino Pyridine N—Oxide

1INTRODUCTIONComplexesofpyridineN-oxideligandshavereceivedmoreandmoreattention,andwehavereportedsomeofthemcontainingadonorsubstituteatthe2-positioninanattempttobroadentherangeofpyridineN-oxidecomplexes[1,2].MostcrystalstructuresofpyridineN-oxidesreportedareaboutdivalenttransitionmetalionsM(Ⅱ)[1～4],withonlyaveryfewontrivalenttransitionmetalionsM(Ⅲ)[5].Asthecontinuingworkofsystematicresearch,herewewillpresentthesynthesisandstructureofthetitlecompound.Toourknowledge,itisthefirstexamplet…     

Bis(2,2′‐bipyridine)iodo­(oxo)tri‐μ3‐sulfido‐tricopper(I)tungsten(VI)

The title nest‐shaped cluster, [Cu₃WIOS₃(C₁₀H₈N₂)₂], has been synthesized by the reaction of (NH₄)₂[WOS₃], CuI and 2,2′‐bipyridine (bipy) in dimethyl­formamide under a purified nitro­gen atmosphere. The cluster has a neutral skeleton containing the bipy ligands, and the central W atom is tetra­hedrally coordinated by three S atoms and one O atom. The three Cu atoms are divided into two different kinds. Two Cu atoms adopt distorted tetra­hedral geometry, with each Cu atom coordinated by two S atoms and the two N atoms of a bipy ligand. The other Cu atom adopts a trigonal mode surrounded by two S atoms and one I atom.     

Neptunium thiophosphate chemistry: intermediate behavior between uranium and plutonium

Black crystals of Np(PS(4)), Np(P(2)S(6))(2), K(11)Np(7)(PS(4))(13), and Rb(11)Np(7)(PS(4))(13) have been synthesized by the reactions of Np, P(2)S(5), and S at 1173 and 973 K; Np, K(2)S, P, and S at 773 K; and Np, Rb(2)S(3), P, and S at 823 K, respectively. The structures of these compounds have been characterized by single-crystal X-ray diffraction methods. Np(PS(4)) adopts a three-dimensional structure with Np atoms coordinated to eight S atoms from four bidentate PS(4)(3-) ligands in a distorted square antiprismatic arrangement. Np(PS(4)) is isostructural to Ln(PS(4)) (Ln = La-Nd, Sm, Gd-Er). The structure of Np(P(2)S(6))(2) is constructed from three interpenetrating diamond-type frameworks with Np atoms coordinated to eight S atoms from four bidentate P(2)S(6)(2-) ligands in a distorted square antiprismatic geometry. The centrosymmetric P(2)S(6)(2-) anion comprises two PS(2) groups connected by two bridging S centers. Np(P(2)S(6))(2) is isostructural to U(P(2)S(6))(2). A(11)Np(7)(PS(4))(13) (A = K, Rb) adopts a three-dimensional channel structure built from interlocking [Np(7)(PS(4))(13)](11-)-screw helices with A cations residing in the channels. The structure of A(11)Np(7)(PS(4))(13) includes four crystallographically independent Np atoms. Three are connected to eight S atoms in bicapped trigonal prisms. The other Np atom is connected to nine S atoms in a tricapped trigonal prism. A(11)Np(7)(PS(4))(13) is isostructural to A(11)U(7)(PS(4))(13). From Np-S bond distances and charge-balance, we infer that Np is trivalent in Np(PS(4)) and tetravalent in Np(P(2)S(6))(2) and A(11)Np(7)(PS(4))(13). Np exhibits a behavior intermediate between U and Pu in its thiophosphate chemistry.     

Synthesis and Crystal Structure of a Mixed Cu - Cd Bim etallic Com plex ｛〔 Cu Cd(pba)( H_2 O)_3〕·2 H_2 O｝ _n

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Synthesis,Crystal Structure and Luminescent Properties of [Ag（bzdmpymt）]6·2MeOH （bzdmpymtH = 5-Benzyl-4,6-dimethylpyrimidine-2-thione）

Reaction of AgAc with bzdmpymtH in MeOH resulted in the title compound [Ag（bzdmpymt）]6-2MeOH （1.2MeOH）, which was structurally characterized by elemental analysis, IR, and single-crystal X-ray diffraction analysis. 1.2MeOH belongs to the triclinic system, space group Pi, with a = 10.930（2）, b = 11.646（2）, c = 16.794（3）A, a = 103.97（3）, β = 97.07（3）, γ = 97.94（3）°, V = 2027.2（7） A3, Z = 1, μ = 1.629 mm^-1, Dc = 1.710 mg/m3, T = 193（2） K, CsoH86Ag6N12O2S6, Mr = 2087.25, F（000） = 1044, S = 1.034, R = 0.0355 and wR = 0.0709. In 1.2MeOH, six silver（I） atoms are held together by six bzdmpymt ligands through N and S atoms to form a water-wheel-shaped structure. Each Ag atom is coordinated by two S atoms from two bzdmpymt ligands and one N atom from the third bzdmpymt ligand, giving a trigonal planar coordination geometry. Interactions between the CH3 group of bzdmpymt ligand and one pyrimidyl nitrogen atom in an adjacent molecule afford a one-dimensional hydrogen-bonding chain running along the b axis. The luminescent property of 1.2MeOH was also investigated.     

Synthesis, Crystal Structure and Luminescent Properties of the Indium(Ⅲ) Complex Based on 2,6-Bis(1-phenylbenzimidazol-2-yl)pyridine

The complex [In(bpbp)Cl3]·H2O, where bpbp is 2,6-bis(1-phenylbenzimidazol- 2-yl)-pyridine (bpbp), was synthesized and characterized by X-ray single-crystal structure analysis. For the complex: C31H21Cl3InN5·H2O, Mr = 702.71, monoclinic, space group, P21/n, a = 9.3918(10), b = 21.024(2), c = 14.5323(15), β = 96.938(2)°, V = 2848.4(5)3, Z = 4, Dc = 1.639 g/cm3, λ = 0.71073, μ(MoKα) = 1.147 mm-1, F(000) = 1408, S = 1.00, R = 0.0430 and wR = 0.1438 for 4620 observed reflections with Ⅰ > 2σ(Ⅰ). It is a neutral complex. The In(Ⅲ) ion adopts a distorted trigonal bipyramidal geometry coordinated by three nitrogen atoms of the ligand and three chlorine atoms. The complex emits blue luminescence with emission peaks at 430 nm in the solid state.     

Synthesis and Crystal Structure of a Mixed Cu-Cd Bimetallic Complex {[CuCd(pba)(H2O)3]·2H2O}n

A one-dimensional bimetallic compound {[CuCd(pba)(H2O)3]·2H2O}n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombic system, molecular formula CuCdC7H16N2O11, Mr=480.17, space group Pnma(#62), a=12.953(2), b=21.626(6), c=5.253(3)(A), V=1471(2)(A)3 and Dx=2.17g/cm3 for Z=4. The structure was solved by direct methods with final R=0.052 and Rw=0.063 for 1055 observed reflections with I>3σ(I). Two nitrogen atoms and two oxygen atoms from the oxamide and a water molecule coordinated to the CuII ion forming a square pyramidal geometry. Four oxygen atoms from the oxamide and two water molecules coordinated to the CdII ion forming an elongated octahedral geometry.