Two novel Keggin tungstocobaltates grafted by cobaltII complex group(s): K[Co(phen)2(H2O)]2[HCoW12O40]·2H2O and [Co(2,2′-bipy)3]1.5{[Co(2,2′-bipy)2(H2O)][HCoW12O40]}·0.5H2O

Two novel inorganic–organic hybrid compounds composed of Keggin tungstocobaltate framework and cobalt(II)–N coordination complexes, K[Co(phen)₂(H₂O)]₂[HCoW₁₂O₄₀]·2H₂O (1) (phen = 1,10-phenanthroline) and [Co(2,2′-bipy)₃]_1.5{[Co(2,2′-bipy)₂(H₂O)][HCoW₁₂O₄₀]·0.5H₂O (2) (bipy = bipyridine), have been synthesized under hydrothermal conditions by directly using Keggin POMs as starting materials, which were characterized by elemental analyses, IR, TG analyses and X-ray single crystal diffraction. Crystal data for compound 1: C₄₈H₄₁Co₃KN₈O₄₄W_12, triclinic, space group P-1, a = 10.918(5) Å, b = 13.401(5) Å, c = 13.693(5) Å, α = 69.291(5)°, β = 71.568(5)°, γ = 78.421(5)°, V = 1768.9(12) Å³, Z = 1; for compound 2: C₁₃₀H₁₀₄Co₇N₂₆O₈₃W_24, orthorhombic, space group, C2/c, a = 46.839(9) Å, b = 14.347(3) Å, c = 26.147(5) Å, α = β = γ = 90°, V = 17,570(6) Å³, Z = 4. Compound 1 exhibits a pseudo-1D chainlike structure, in which potassium ions act as linkages of Keggin unit doubly grafted by [Co(phen)₂(H₂O)] complex. Compound 2 represents a [Co(2,2′-bipy)₂(H₂O)]²⁺ mono-grafted Keggin tungstocobaltate derivative with 1.5[Co(2,2′-bipy)₃]²⁺ countercations. The cyclic voltammetric behavior of 1-CPE is similar to the parent 3-CPE, but the cyclic voltammetric behavior of Co^II shows a little difference. Variable-temperature magnetic susceptibility measurement of compound 1 demonstrates the presence of antiferromagnetic interactions.     

Ce(H2O)(PO4)3/2(H3O)1/2(H2O)1/2, a second entry in the structural chemistry of cerium(IV) phosphates

A cerium(IV) phosphate has been prepared using precipitation methods and its structure has been solved by single crystal X-ray diffraction (R₁ = 0.0292 for 3092 reflections with I>2σ(I) and wR₂ = 0.0540). Ce(H₂O)(PO₄)_3/2(H₃O)_1/2(H₂O)_1/2 crystallises in the monoclinic space group C2/c (a = 15.7058(17) Å, b = 9.6261(9) Å, c = 10.1632(4) Å, ß = 121.623(7)°, and V = 1308.4 (2) Å³). Its structure is based on a negatively charged 3D framework, made of cerium atoms connected by PO₄ tetrahedra. There are two types of PO₄ units; one shares only corners with the cerium coordination polyhedra while the other one shares edges and corners. This structure also includes hydronium cations, to balance the framework charge, and water molecules. One special feature of this 3D framework is the formation of interconnected tunnels which extend along the c axis and contain the hydronium cations and the water molecules. This open framework and the presence of cationic species in the tunnels are in perfect agreement with the previously reported ion exchange properties.     

Synthesis and characterization of a novel three-dimensional open-framework: Metal diphosphonate,Zn[HO3PCH2(C6H4)CH2PO3H]

A novel zinc diphosphonate, Zn[HO₃PCH₂(C₆H₄)CH₂PO₃H] (1) was synthesized from tetraethyl para-xylylenediphosphonate, Et₂O₃PCH₂C₆H₄CH₂PO₃Et₂, and Zn (AcO)₂·2H₂O under solvothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction, which reveals that the structure crystallizes in the monoclinic space group C2/c (No. 15), with a = 22.4844(19) Å, b = 6.4361(5) Å, c = 8.1194(7) Å, β = 102.595(2)°, V = 1146.70(16) Å³, T = 298(2) K, Z = 8. The novel three-dimensional (3D) construction is simply built up from linear inorganic chains of corner-sharing four-rings of tetrahedral [ZnO₄] and [PO₃C] which connected adjacent chains by the organophosphorus ligand para-xylylenediphosphonate. The framework has 10 Å × 4 Å (containing the van der Waals radii of atoms) channels running along the b-axis.     

Copper and cadmium phosphonates based on 2-quinolinephosphonate

Hydrothermal reactions of 2-quinolinephosphonic acid (1) and CuSO₄ or CdSO₄ result in two new compounds with formula Cu(2-C₉H₆NPO₃) (2) and Cd(2-C₉H₆NPO₃)(H₂O) (3). Compound 2 has a layer structure in which dimers of edge-sharing {CuO₄N} square-pyramids are linked by {CPO₃} tetrahedra through corner sharing. Compound 3 shows a new type of layer structure where chains of corner sharing {CdO₅N} octahedra are connected by {CPO₃} tetrahedra into an inorganic layer. The quinoline groups fill in the inter-layer spaces in both cases. Crystal data for 1: monoclinic, space group P2₁/c, a = 10.270(2) Å, b = 13.566(3) Å, c = 6.9818(16) Å, β = 101.916(4)°, V = 951.8(4) Å³, Z = 4. For 2: monoclinic, space group P2₁/c, a = 13.976(3) Å, b = 7.9398(18) Å, c = 7.8687(18) Å, β = 101.150(5)°, V = 856.7(3) Å³, Z = 4. For 3: monoclinic, space group P2₁/c, a = 17.164(4) Å, b = 5.4870(12) Å, c = 10.850(2) Å, β = 101.557(4)°, V = 1001.1(4) Å³, Z = 4. The magnetic measurement on 2 reveals a dominant antiferromagnetic exchange coupling between the Cu(II) centers. A quasi-reversible electrochemical reaction is observed for complex 2 immobilized on the surface of GC electrode, corresponding to the redox couple Cu²⁺/Cu⁺. The fluorescent properties of 1–3 are also investigated.     

Comparative study of two layered lanthanide dicarboxylates based on europium(III) dimers

The new rare-earth dicarboxylate solid Eu₂(H₂O)₄{C₆H₁₀–(CO₂)₂}₃·2H₂O or MIL-94 has been isolated under hydrothermal conditions. Its layered structure, which was solved using X-ray powder diffraction data, is built up from dimers of nine-coordinated edge-sharing polyhedra linked through 1,3-cyclohexane dicarboxylate (1,3-CHC) moieties. A comparative study of MIL-94 and the layered lanthanide dicarboxylate EuBDC or Eu₂(H₂O)₂{C₆H₄–(CO₂)₂}₃, which is built up from dimers of corner-sharing polyhedra and 1,3-benzenedicarboxylate (1,3-BDC) linkers, is also reported. Crystal data for MIL-94: orthorhombic space group Pnma (no. 62) with a = 8.8470(1) Å, b = 25.0148(1) Å, c = 14.3716(4) Å and Z = 4. MIL stands for Material Institut Lavoisier.     

The dimeric unit [La(H2O)4(m-PO3C6H4COOH)(m-PO2(OH)C6H4COOH)(m-PO(OH)2C6H4COOH)]2 as building block of layered hybrid material

A new hybrid organic–inorganic material with the structural formula unit [La(H₂O)₄(m-PO₃C₆H₄COOH)(m-PO₂(OH)C₆H₄COOH)(m-PO(OH)₂C₆H₄COOH)]₂ (or [La(H₂O)₄C₂₁H₁₈O₁₅P₃]₂) has been synthesized under hydrothermal condition from La(NO₃)₃·6H₂O and 3-phosphonobenzoic acid (m-PO(OH)₂–C₆H₄–COOH) which is a rigid organic precursor possessing two types of functional groups: phosphonic acid and carboxylic acid. The two units of the produced hybrid are linked together by hydrogen bonds leading to a layered framework composing of by a repetition of inorganic and organic slices. The organic layers consist of dimeric units made of two meta-phosphono-benzoic acid linked together by hydrogen bonds involving their COOH groups. Two kinds of dimeric units are observed: PO₃C₆H₄COOH?HOOCC₆H₄PO(OH)₂, present 2 times in the structure, and PO₂(OH)C6H4COOH?HOOCC₆H₄PO₂(OH). The material crystallises in a monoclinic cell (C2/c (15) space group) with the following parameters: a = 42.515(4) Å, b = 7.4378(6) Å, c = 20.307(2) Å, β = 118.031(6)°, V = 5668.2(9) Å³, Z = 4, density = 1.908 g/cm³.     

Controlling the dimensionality of oxalate-based bimetallic complexes: The ferromagnetic chain {[K(18-crown-6)][Mn(bpy)Cr(ox)3]}∞(18-crown-6 = C12H24O6, ox=C2O42-, bpy = C10H8N2)

The bimetallic ferromagnetic chain {[K(18-crown-6)][Mn(bpy)Cr(ox)₃]}_∞ (1) has been synthesized and characterized. It crystallizes in the orthorhombic chiral space group P2₁2₁2₁ [a = 9.0510(2) Å, b = 14.4710(3) Å, c = 26.8660(8) Å, V = 3510.97(1) Å³, Z = 2]. Compound 1 is made up by anionic [Mn(bpy)Cr(ox)₃]⁻ 1D chains and cationic [K(18-crown-6)]⁺ complexes. The magnetic exchange within the chain is ferromagnetic [J = +7.8(7) cm⁻¹]. In the solid state, the ferromagnetic chains are well isolated magnetically and no long range magnetic ordering has been observed above 2 K.     

The crystal structure of potassium ammonium hexamolybdotellurate with telluric acid K5NH4[TeMo6O24].Te(OH)6.6H2O

An inorganic compound formulated as K₅NH₄[TeMo₆O₂₄].Te(OH)₆.6H₂O (1) has been isolated by conventional solution method and structurally characterized by single-crystal X-ray diffraction methods, scanning electron microscopy (SEM), IR, UV–vis spectra, and cyclic voltammetry measurements. This compound crystallizes in the monoclinic system, space group C2/c with unit a = 18.6841(1) Å, b = 10.0513(1) Å, c = 21.1065(1) Å, β = 116.495(1)°, V = 3547.49(4) ų, Z = 4, R = 0.033 and wR (F²) = 0.087 for 3432 unique observed reflexions [I > 2σ(I)]. The crystal structure of (1) is built up from an Anderson clusters connected through hydrogen-bonding interactions into a three-dimensional supramolecular network.     

New metastable hybrid phase,Zn2(OH)2(C8H4O4), exhibiting unique oxo-penta-coordinated Zn(II) atoms

The metastable phase (phase 1) Zn(OH)₂(tp)₂ (tp = C₈H₄O₄^2?) was found to be an intermediate forming during the hydrothermal synthesis of Zn₃(OH)₄tp (phase 2). Its structure has been determined ab initio from synchrotron powder diffraction data and refined with the Rietveld method: space group P2₁/c, a = 3.48856(2) Å, b = 5.84645(2) Å, c = 22.1331(1) Å, β = 103.46(1)°, D_x = 2.488 g/cm³, R_p = 0.10, R_B = 0.095 (402 independent reflections). The structures of the two analogues were compared. Whereas a mixed coordination of the zinc atoms was found in phase 2, phase 1 exhibits only penta-coordinated Zn(II). Moreover, different optical properties were observed, Zn₂(OH)₂(tp) showing photoluminescence at 378 nm under λ_ex = 316 nm.     

Solvothermal synthesis and crystal structure of the Mo(VI)-bridged helical chain containing Mo2(V) dimers: (C4H12N2)2[(MoV2O4)(MoVIO4)(C2O4)2]·2H2O

A new molybdenum complex (C₄H₁₂N₂)₂[(Mo^V₂O₄)(Mo^VIO₄)(C₂O₄)₂]·2H₂O, was solvothermally synthesized and characterized by single-crystal X-ray diffraction. The structure of the compound consists of oxalate acid-coordinated mixed-valent [Mo^V₂O₄][Mo^VIO₄] helical chains and protonated piperazine cations. The helical chains are built up from the [Mo^V₂O₄] units and [Mo^VIO₄] tetrahedral. The central axis about helical chain is a 2-fold screw axis. The compound crystallizes in the space group P2₁/n of monoclinic system with a = 11.396(2) Å, b = 14.107(3) Å, c = 15.805(3) Å, β = 102.09(3)°, V = 2484.6(9) Å³, Z = 4. Other characterizations by elemental analysis, IR, and thermal analysis for this compound are also given.     

Synthesis,crystal structure,and magnetic properties of K4Mn3(HPO4)4(H2PO4)2

A new layered compound, K₄Mn₃(HPO₄)₄(H₂PO₄)₂ (1), has been synthesized under hydrothermal conditions. It crystallizes in the monoclinic space group P2₁/n with a = 8.874(2) Å, b = 6.554(1) Å, c = 18.075(4) Å, and β = 93.39(3)°. The structure consists of zigzag [Mn₃O₁₄]_n chains of edge-sharing MnO₆ octahedrons and MnO₇ pentagonal bi-pyramids, which form layers of formula [Mn₃(HPO₄)₄(H₂PO₄)₂]^4? in the ab plane via H₂PO₄ and HPO₄ units with vertex-sharing. Potassium ions lie between these layers. Magnetic measurements indicate Curie–Weiss behavior above 6 K for 1. A Heisenberg model, with alternating exchange interactions J₁J₁J₂… within the chain and exchange interactions J₃J₃… between the chains, is proposed to describe the magnetic behavior.     

New three-dimensional (3,4)-net zincophosphites templated by linear diammonium cations: H3N(CH2)5NH3·Zn3(HPO3)4 and β-H3N(CH2)6NH3·Zn3(HPO3)4

The mild-condition syntheses, single-crystal structures and properties of H₃N(CH₂)₅NH₃·Zn₃(HPO₃)₄ and β-H₃N(CH₂)₆NH₃·Zn₃(HPO₃)₄ are reported. Both are constructed from (3,4)-nets of ZnO₄ tetrahedra and HPO₃ pyramids, sharing vertices to result in three-dimensional anionic open-frameworks. In both materials, the organic species interacts with the framework by way of N–H⋯O bonds. Crystal data: H₃N(CH₂)₅NH₃·Zn₃(HPO₃)₄, M_r = 620.22, orthorhombic, Pccn (No. 56), a = 9.5364 (9) Å, b = 21.8015 (19) Å, c = 9.1118 (7) Å, V = 1894.4 (3) Å³, Z = 4, R(F) = 0.044, wR(F²) = 0.111. β-H₃N(CH₂)₆NH₃·Zn₃(HPO₃)₄, M_r = 634.25, monoclinic, P2₁/n (No. 14), a = 8.7627 (1) Å, b = 13.8117 (2) Å, c = 16.6187 (3) Å, β = 92.680 (1)°, V = 2009.12 (5) Å³, Z = 4, R(F) = 0.072, wR(F²) = 0.187.     

Synthesis,crystal structure and thermal behaviour of [La(hfa)3(Phen)2] (hfa = hexafluoroacetylacetonate,Phen = o-phenanthroline)

The mixed ligand complex [La(hfa)₃(Phen)₂] (I) was obtained by the interaction of La(hfa)₃ and Phen; its composition does not depend on the stoichiometry of the reagents. According to the X-ray single crystal analysis data, complex I crystallizes in the monoclinic space group P2₁/n, with a = 13.583(3) Å, b = 16.959(3) Å, c = 18.860(4) Å, β = 94.71(3)° and Z = 4. The structure of I consists of isolated mononuclear molecules, the coordination number of La being 10. Thermal behaviour and composition of the vapor phase have been studied for I by thermal analysis and mass-spectrometry using a Knudsen cell. The mixed ligand complex I was found to sublime congruently in the temperature range 370–460 K: [La(hfa)₃(Phen)₂]_(s) = [La(hfa)₃(Phen)]_(g) + Phen_(g), Δ_rH⁰(T) = 316.2 ± 1.8 kJ/mol.     

Synthesis,X-ray structure and reactivity of μ-(CF3COO)2-[Mo(N-2,6-i-Pr2-C6H3)(CHCMe2Ph)(OOCCF3)(Et2O)]2, the first Bis(trifluoroacetate) derivative of a Schrock catalyst

Reaction of Mo(N-2,6-i-Pr₂-C₆H₃)(CHCMe₂C₆H₅)(OSO₂CF₃)(DME) (DME = 1,2-dimethoxyethane) with 2 equiv. of CF₃COOK yields μ-(CF₃COO)₂-[Mo(N-2,6-i-Pr₂-C₆H₃)(CHCMe₂Ph)(OOCCF₃)(Et₂O)]₂ (1). Compound 1 crystallizes in the orthorhombic space group Pna2₁ with a = 17.2485(3), b = 17.0336(3), c = 25.4031(5) Å, α = β = γ = 90°, V = 7463.5(2) Å³, Z = 4. In contrast to alkoxide based Schrock type initiators, 1 is virtually inactive in numerous metathesis reactions including ring-closing metathesis (RCM) and homo metathesis reactions, the cyclopolymerization of 1,6-heptadiynes, and even ring-opening metathesis polymerization (ROMP) of norborn-2-ene. However, addition of quinuclidine results in the in situ formation of 1a (Mo(N-2,6-i-Pr₂-C₆H₃)(CHCMe₂C₆H₅)(OOCCF₃)₂(quinuclidine) which displays moderate activity in ROMP, cyclopolymerization of 1,6-heptadiynes and RCM. Theoretical investigations carried out on the B3LYP/LACVP¹ level provide substantial explanation for these findings.     

[H4tren]3/2·(Al6F24)·3H2O,the most condensed fluoride in the Al(OH)3-tren-HFaq.-ethanol system

The most condensed crystalline fluoride that appears in the Al(OH)₃-tren-HF_aq.-ethanol system at 190 °C is found to be [H₄tren]_3/2·(Al₆F₂₄)·3H₂O. The structure is monoclinic, P2₁/c, with a = 21.939(1) Å, b = 6.7180(2) Å, c = 23.329(1) Å, β = 111.324(2)°. _∞(Al₆F₂₄) chains result from the connection of (Al₇F₃₀)⁹⁻ polyanions by opposite AlF₆ octahedra. Hydrogen bonds are established between the _∞(Al₆F₂₄) chains and ordered or disordered [H₄tren]⁴⁺ cations and water molecules.     

Crystal structures of Th(OH)PO4, U(OH)PO4 and Th2O(PO4)2. Condensation mechanism of MIV(OH)PO4 (M = Th,U) into M2O(PO4)2

Three new crystal structures, isotypic with β-Zr₂O(PO₄)₂, have been resolved by the Rietveld method. All crystallize with an orthorhombic cell (S.G.: Cmca) with a = 7.1393(2) Å, b = 9.2641(2) Å, c = 12.5262(4) Å, V = 828.46(4) Å³ and Z = 8 for Th(OH)PO₄; a = 7.0100(2) Å, b = 9.1200(2) Å, c = 12.3665(3) Å, V = 790.60(4) Å³ and Z = 8 for U(OH)PO₄; a = 7.1691(3) Å, b = 9.2388(4) Å, c = 12.8204(7) Å, V = 849.15(7) Å³ and Z = 4 for Th₂O(PO₄)₂. By heating, the M(OH)PO₄ (M = Th, U) compounds condense topotactically into M₂O(PO₄)₂, with a change of the environment of the tetravalent cation that lowers from 8 to 7 oxygen atoms. The lower stability of Th₂O(PO₄)₂ compared to that of U₂O(PO₄)₂ seems to result from this unusual environment for tetravalent thorium.     

Copper(II)-methylmalonate complexes with unidentate N-donor ligands: Syntheses,structural characterization and magnetic properties

Two new methylmalonate-bridged copper(II) complexes with the formulas [Cu(3-Ipy)(Memal)(H₂O)] (1) and [Cu(2,4′-bpy)(Memal)(H₂O)] · 3H₂O (2) [Memal = methylmalonate dianion, 3-Ipy = 3-iodopyridine, 2,4′-bpy = 2,4′-bipyridine] have been synthesized and characterized by X-ray diffraction. Both compounds crystallize in the monoclinic space group P2₁/n and Z = 4, with unit cell parameters a = 8.5874(13) Å, b = 7.1738(14) Å, c = 19.093(5) Å, β = 99.509(15)° in 1 and a = 17.375(4) Å, b = 7.3305(14) Å, c = 14.247(3) Å, β = 111.409(15)° in 2. The structures of 1 and 2 consist of zigzag chains of anti-syn carboxylate-bridged copper(II) ions running along the b direction. The pyridine-like ligands occupy one equatorial position of the copper environment avoiding the formation of the sheet-like arrangement observed in previously reported Memal complexes. The chains are grouped together in hydrophilic layers through hydrogen bonds and the layers are pillared through the 3-Ipy (1) and 2,4′-bpy (2) ligands which are stacked through π–π interactions involving alternatively aromatic ligands from two adjacent chains. Magnetic susceptibility measurements of both compounds in the temperature range 2–290 K show the occurrence of intrachain ferromagnetic interactions between the copper(II) ions [J = +2.66(2) cm^?1 (1) and J = +2.62(2) cm^?1 (2)].     

Synthesis and structure of a bimetallic hybrid inorganic/organic layered coordination polymer with an octamolybdate cluster variant trapped between the α and δ isomeric forms

Hydrothermal combination of CuSO₄, MoO₃, and 4-phenylpyridine (4-phpyr) in a 1:4:4.5 ratio under basic conditions afforded purple crystals of {[Cu(4-phpyr)₄]₂(Mo₈O₂₆)·4-phpyr} (1), which were analyzed by spectroscopy and single crystal X-ray diffraction. The asymmetric octamolybdate clusters in 1 adopt an intermediate structural variant between the known α and δ isomeric forms, with four octahedral and three tetrahedral molybdenum coordination spheres, along with one molybdenum atom in a highly distorted square pyramidal environment. Paddle-wheel shaped [Cu(4-phpyr)₄]²⁺ cations link adjacent {α/δ-Mo₈O₂₆}⁴⁻ clusters into a 2-D layered rhomboid grid coordination polymer. Uncoordinated 4-phpyr molecules lie in incipient voids in the interlamellar regions. The structure of 1 illustrates the utility of sterically bulky coordination complexes in the stabilization of intermediate conformations during energetically facile polyoxometallate isomer interconversion. Crystallographic data: triclinic, P1, a = 13.717(3) Å, b = 13.728(3) Å, c = 14.809(3) Å, α = 109.251(4)°, β = 107.670(4)°, γ = 92.005(4)°, V = 2480.0(9) Å³, R₁ = 0.0637, wR₂ = 0.1054.     

A new potassium rare earth oxyborate K2La2(BO3)2O

A series of potassium rare earth oxyborates, K₂RE₂(BO₃)₂O (RE = La, Nd, Sm and Eu), have been synthesized. Single crystal of the first member of the series, K₂La₂(BO₃)₂O, has been grown by the flux method. Its structure, determined by single crystal X-ray diffraction, shows that it belongs to the monoclinic system, space group P2₁/c with unit cell parameters of a = 11.422(2) Å, b = 6.6803(13) Å, c = 10.813(2) Å, β = 17.23(3)° and Z = 4. Optical transmission spectrum shows that the K₂La₂(BO₃)₂O crystal is highly transparent from 215 nm to 2750 nm.     

Electrochemical and magnetic properties of inorganic polymers constructed from Mn(II)/Co(II)-substituted heteropolymolybdates

Two inorganic polymers constructed from transition metal-substituted heteropolymolybdates, [(CH₃)₃NH]_5n[PMo₁₁MO₃₉]_n·xH₂O (M = Mn²⁺, x = n (1); M = Co²⁺, x = 2n (2)), have been synthesized in aqueous solutions and characterized by IR, TGA, and single-crystal X-ray diffraction analysis. Crystal data: 1, monoclinic, C2/c, a = 17.1322(7) Å, b = 17.6062(7) Å, c = 17.6459(7) Å, β = 103.2220(10)°, V = 5181.5(4) Å³ and Z = 4; 2, triclinic, P-1, a = 12.1986(7) Å, b = 13.0973(7) Å, c = 16.7736(9) Å, α = 97.1810(10)°, β = 98.5040(11)°, γ = 96.3920(10)°, V = 2606.5(2) Å³ and Z = 2. The cyclic voltammograms of 1 and 2 show irreversible redox peaks in DMF solution and there are three reversible couples after addition of 0.1 M H₂SO₄ aqueous solutions. The cyclic voltammograms of 1/2-modified carbon paste electrode (1-CPE/2-CPE) show two consecutive reversible two-electron redox processes. Especially, 2-CPE shows good electrocatalytic activity toward the reduction of nitrite and hydrogen peroxide. The magnetic properties of the two complexes have also been investigated.