[Cr(phen)(ox)2]-: a versatile bis-oxalato building block for the design of heteropolymetallic systems. Crystal structures and magnetic properties of AsPh4[Cr(phen)(ox)2]·H2O, [NaCr(phen)(ox)2(H2O)]·2H2O and {[Cr(phen)(ox)2]2[Mn2(bpy)2(H2O)2(ox)]}·6H2O

The new complexes of formula AsPh4[Cr(phen)(ox)2]·H2O (1), [NaCr(phen)(ox)2(H2O)]·2H2O (2) and {[Cr(phen)(ox)2]2[Mn2(bpy)2(H2O)2(ox)]}·6H2O (3) (AsPh4=tetraphenylarsonium cation; phen=1,10-phenanthroline; ox=oxalate dianion; bpy=2,2′-bipyridine) have been prepared and characterized by single-crystal X-ray diffraction. The structure of 1 consists of discrete [Cr(phen)(ox)2]− anions, tetraphenylarsonium cations and uncoordinated water molecules. The chromium environment in 1 is distorted octahedral with Cr–O bond distances between 1.959(3) and 1.947(3) A and Cr–N bonds of 2.083(4) and 2.072(4) A. The angles subtended at the chromium atom by the two oxalates are 83.6(2) and 83.3(1)° whereas th…

Rational design of a new class of heterobimetallic molecule-based magnets: Synthesis, crystal structures, and magnetic properties of oxamato-bridged (M′=LiI and MnII; M=NiII and CoII) open-frameworks with a three-dimensional honeycomb architecture

Abstract Two new series of oxamato-bridged heterobimetallic coordination networks of general formula Li5[Li3M2(mpba)3(H2O)6] · 31H2O [M = NiII (1a) and CoII (1b)] and Li2[Mn3M2(mpba)3(H2O)6] · 22H2O [M = NiII (2a) and CoII (2b)] have been prepared from the metal-mediated self-assembly of the hexakis(bidentate), triple-stranded dinickel(II) and dicobalt(II) complexes [M2(mpba)3]8− [mpba = meta-phenylenebis(oxamato)] with either monovalent lithium(I) or divalent manganese(II) ions respectively, in water. X-ray structural analyses of 1a and 1b show an anionic three-dimensional network formed by an infinite parallel array of oxamato-bridged Li 3 I M 2 II (M = Ni and Co) hexagonal layers, which …

[Cr(dpa)(ox)2]–: a new bis-oxalato building block for the design of heteropolymetallic systems. Crystal structures and magnetic properties of PPh4[Cr(dpa)(ox)2], AsPh4[Cr(dpa)(ox)2], Hdpa[Cr(dpa)(ox)2]·4H2O, Rad[Cr(dpa)(ox)2]·H2O and Sr[Cr(dpa)(ox)2]2·8H2O (dpa = 2,2′-dipyridylamine)

[EN] The new complexes of formulae PPh4[Cr(dpa)(ox)(2)] (1), AsPh4[Cr(dpa)(OX)(2)] (2), Hdpa[Cr(dpa)(ox)(2)]-4H(2)O (3), Rad[Cr(dpa)(ox)(2)] . H2O (4) and Sr[Cr(dpa)(ox)(2)](2) . 8H(2)O (5) [PPh4 = tetraphenylphosphonium cation; AsPh4 = tetraphenylarsoniurn cation; dpa = 2,T-dipyridylamine; ox = oxalate dianion; Rad = 2-(4-N-methylpyridinium)4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-a-oxyl-3-N-oxide] have been prepared and characterised by single-crystal X-ray diffraction. The structures of 1-4 consist of discrete [Cr(dpa)(ox)(2)](-) anions, tetraphenylphosphonium. (1), tetraphenylarsonium (2), monoprotonated Hdpa (3) and univalent radical (4) cations and uncoordinated water molecules (2-…

[Cr(bpym)(C2O4)2]− in designing heterometallic complexes. Crystal structures and magnetic properties of PPh4[Cr(bpym)(C2O4)2]·H2O and [Ag(bpym)][Cr(C2O4)2](H2O)2]·2H2O (bpym=2,2′-bipyrimidine)

Abstract The preparation, crystal structure and magnetic properties of PPh 4 [Cr(bpym)(C 2 O 4 ) 2 ]·H 2 O ( 1 ) and [Ag(bpym)][Cr(C 2 O 4 ) 2 (H 2 O) 2 ]·2H 2 O ( 2 ) (C 2 O 4  2− =oxalate dianion, bpym=2,2′-bipyrimidine and PPh 4  + =tetraphenylphosphonium cation) are described. The structure of 1 is made up of discrete (2,2′-bipyrimidine)bis(oxalato)chromate(III) anions, teraphenylphosphonium cations and uncoordinated water molecules. The structure of 2 consists chains of univalent silver cations bridged by bis-chelating 2,2′-bypyrimidine, cis -diaquabis(oxalato)chromate(III) anions and crystallisation water molecules. The chromium atom in 1 and 2 has a slightly distorted octahedral geom…

Field-induced single ion magnet behaviour of discrete and one-dimensional complexes containing [bis(1-methylimidazol-2-yl)ketone]-cobalt(II) building units.

International audience; We describe herein the first examples of six-coordinate CoII single-ion magnets (SIMs) based on the β-diimine Mebik ligand [Mebik = bis(1-methylimidazol-2-yl)ketone]: two mononuclear [CoII(Rbik)2L2] complexes and one mixed-valence {CoIII2CoII}n chain of formulas [CoII(Mebik)(H2O)(dmso)(μ-NC)2CoIII2(μ-2,5-dpp)(CN)6]n·1.4nH2O (3) [L = NCS (1), NCSe (2) and 2,5-dpp = 2,5-bis(2-pyridyl)pyrazine (3)]. Two bidentate Mebik molecules plus two monodentate N-coordinated pseudohalide groups in cis positions build somewhat distorted octahedral surroundings around the high-spin cobalt(II) ions in 1 and 2. The diamagnetic [CoIII2(μ-2,5-dpp)(CN)8]2− metalloligand coordinates the pa…

Solid‐State Anion–Guest Encapsulation by Metallosupramolecular Capsules Made from Two Tetranuclear Copper(II) Complexes

A new cationic tetranuclear copper(II) complex self-assembles from one 1,3-phenylenebis(oxamato) (mpba) bridging ligand and four CuII ions partially blocked with N,N,N′,N′-tetramethylethylenediamine (tmen) terminal ligands. In the solid state, two of these tetracopper(II) oxamato complexes of bowl-like shape and helical conformation then serve as a building block for the generation of either hetero- (MP) or homochiral (MM/PP) dimeric capsules depending on the nature of the encapsulated anion guest, perchlorate or hexafluorophosphate. The overall magnetic behaviour of these metallosupramolecular capsules does not depend on the nature of the encapsulated anion guest, but it is consistent with…

Synthesis, crystal structure and magnetic properties of two oxalato-bridged dimetallic trinuclear complexes combined with a polar cation

Two isostructural heterometallic trinuclear oxalato-bridged complexes of formula C(4)[MCr(2)(ox)(6)(H(2)O)(2)]·nH(2)O (C(+) = 4-aminopyridinium; ox(2-) = oxalate dianion; M(2+) = Mn(2+), n = 3, 1; M(2+) = Co(2+), n = 3.25, 2) have been synthesized by using direct self-assembly methods combining C(3)[Cr(ox)(3)] and the chloride salts of the corresponding metal ion. The crystal structures of both compounds have been resolved by single-crystal X-ray diffraction. They crystallize in the C2/c space group [a = 11.5113(15) Å, b = 20.250(3) Å, c = 21.810(4) Å, beta = 100.447(10) degrees, V = 5161.6(3) Å(3), and Z = 4 for 1, and a = 11.4334(16) Å, b = 20.243(2) Å, c = 21.805(3) Å, beta = 101.113(9) …

Two-Dimensional Assembling of (2,2‘-Bipyrimidine)bis(oxalato)chromate(III) Units through Alkaline Cations

Self-assembling of the tris-chelated [Cr(bpm)(ox)2]- complex with Na+ in aqueous solution leads to the remarkable bimetallic honeycomb layered compound of formula [NaICrIII(bpm)(ox)2]·5H2O (2) (bpm...

Supramolecular coordination chemistry of aromatic polyoxalamide ligands: A metallosupramolecular approach toward functional magnetic materials

Abstract The impressive potential of the metallosupramolecular approach in designing new functional magnetic materials constitutes a great scientific challenge for the chemical research community that requires an interdisciplinary collaboration. New fundamental concepts and future applications in nanoscience and nanotechnology will emerge from the study of magnetism as a supramolecular function in metallosupramolecular chemistry. Our recent work on the rich supramolecular coordination chemistry of a novel family of aromatic polyoxalamide (APOXA) ligands with first-row transition metal ions has allowed us to move one step further in the rational design of metallosupramolecular assemblies of …

Oligo-m-phenyleneoxalamide Copper(II) Mesocates as Electro-Switchable Ferromagnetic Metal–Organic Wires

Double-stranded copper(II) string complexes of varying nuclearity, from di- to tetranuclear species, have been prepared by the CuII-mediated self-assembly of a novel family of linear homo- and heteropolytopic ligands that contain two outer oxamato and either zero (1 b), one (2 b), or two (3 b) inner oxamidato donor groups separated by rigid 2-methyl-1,3-phenylene spacers. The X-ray crystal structures of these CuIIn complexes (n=2 (1 d), 3 (2 d), and 4 (3 d)) show a linear array of metal atoms with an overall twisted coordination geometry for both the outer CuN2O2 and inner CuN4 chromophores. Two such nonplanar all-syn bridging ligands 1 b–3 b in an anti arrangement clamp around the metal ce…

Titelbild: Cyanide-Bridged Iron(III)–Cobalt(II) Double Zigzag Ferromagnetic Chains: Two New Molecular Magnetic Nanowires (Angew. Chem. 13/2003)

Nuclearity controlled cyanide-bridged bimetallic CrIII-MnII compounds: synthesis, crystal structures, magnetic properties and theoretical calculations.

The preparation, X-ray crystallography and magnetic investigation of the compounds PPh4[Cr(bipy)(CN)4].2 CH3CN.H2O (1) (mononuclear), [[Cr(bipy)(CN)4]2Mn-(H2O)4].4H2O (2) (trinuclear), [[Cr(bipy)(CN)4]2Mn(H2O)2] (3) (chain) and [[Cr(bipy)(CN)4]2Mn(H2O)].H2O.CH3CN (4) (double chain) [bipy=2,2'-bipyridine; PPh4 (+)=tetraphenylphosphonium] are described herein. The [Cr(bipy)(CN)4]- unit act either as a monodentate (2) or bis-monodentate (3) ligand toward the manganese atom through one (2) or two (3) of its four cyanide groups. The manganese atom is six-coordinate with two (2) or four (3) cyanide nitrogens and four (2) or two (3) water molecules building a distorted octahedral environment. In 4…

Variation of the ground spin state in homo- and hetero-octanuclear copper(II) and nickel(II) double-star complexes with a meso-helicate-type metallacryptand core.

Homo- and heterometallic octanuclear complexes of formula Na₂{[Cu₂(mpba)₃][Cu(Me₅dien)]₆}-(ClO₄)₆·12H₂O (1), Na₂{[Cu₂(Mempba)₃][Cu(Me₅dien)]₆}(ClO₄)₆·12H₂O (2), Na₂{[Ni₂(mpba)₃]-[Cu(Me₅dien)]₆}(ClO₄)₆·12H₂O (3), Na₂{[Ni₂(Mempba)₃][Cu(Me₅dien)]₆}(ClO₄)₆·9H₂O (4), {[Ni₂(mpba)₃][Ni(dipn)(H₂O)]₆}(ClO₄)₄·12.5H₂O (5), and {[Ni₂(Mempba)₃][Ni(dipn)-(H₂O)]₆}(ClO₄)₄·12H₂O (6) [mpba = 1,3-phenylenebis(oxamate), Mempba = 4-methyl-1,3-phenylenebis(oxamate), Me₅dien = N,N,N',N'',N''-pentamethyldiethylenetriamine, and dipn = dipropylenetriamine] have been synthesized through the "complex-as-ligand/complex-as-metal" strategy. Single-crystal X-ray diffraction analyses of 1, 3, and 5 show cationic M(II)₂M'(I…

Single chain magnet behaviour in an enantiopure chiral cobalt(II)–copper(II) one-dimensional compound

The self-assembly of an enantiomerically pure, chiral dianionic oxamatocopper(II) complex with cobalt(II) ions leads to neutral oxamato-bridged heterobimetallic chains that combine chirality and slow magnetic relaxation, providing thus the first example of ‘‘chiral single chain magnets (CSCMs). Ruiz Garcia, Rafael, Rafael.Ruiz@uv.es ; Lloret Pastor, Francisco, Francisco.Lloret@uv.es

Molecular-Programmed Self-Assembly of Homo- and Heterometallic Tetranuclear Coordination Compounds: Synthesis, Crystal Structures, and Magnetic Properties of Rack-Type CuII2MII2 Complexes (M = Cu and Ni) with Tetranucleating Phenylenedioxamato Bridging Ligands

New homo- and heterobimetallic tetranuclear complexes of formula [Cu4(mpba)(Me4en)4(H2O)4](ClO4)4·3H2O (1), [Cu4(mpba)(Me4en)4(H2O)4](PF6)4·2H2O (2), [Cu4(ppba)(Me4en)4(H2O)4](ClO4)4·2H2O (3), [Cu4(mpba)(dipn)4](ClO4)4·3H2O (4), [Cu4(ppba)(dipn)4](ClO4)4·2H2O (5), and [Cu2Ni2(ppba)(dipn)4(H2O)2](PF6)4 (6) [mpba = N,N′-1,3-phenylenebis(oxamate), ppba = N,N′-1,4-phenylenebis(oxamate), Me4en = N,N,N′,N′-tetramethylethylenediamine, and dipn = dipropylenetriamine] have been synthesized and structurally and magnetically characterized. Complexes 1−6 have been prepared following a molecular-programmed self-assembly method, where a heteropolytopic tetranucleating phenylenedioxamato bridging ligand (…

Rational enantioselective design of chiral heterobimetallic single-chain magnets: synthesis, crystal structures and magnetic properties of oxamato-bridged M(II)Cu(II) chains (M=Mn, Co).

A new series of neutral oxamato-bridged M(II)Cu(II) chiral chains of general formula [MCuL(x)(S)(m)(H(2)O)(n)]·aS·bH(2)O [L(1)=(M)-1,1'-binaphthalene-2,2'-bis(oxamate) with M=Mn (1a) and Co (1b); L(2)=(P)-1,1'-binaphthalene-2,2'-bis(oxamate) with M=Mn (2a) and Co (2b)] and the analogous racemic chains of formula [MCuL(3)(S)(m)(H(2)O)(n)]·aS·bH(2)O [L(3)=1,1'-binaphthalene-2,2'-bis(oxamate) with M=Mn (3a) and Co (3b)] have been prepared by reaction of the corresponding dianionic oxamatocopper(II) complex [Cu(L(x))](2-) with Mn(2+) or Co(2+) cations in either dimethylformamide (DMF) or dimethyl sulfoxide (DMSO). Solid circular dichroism (CD) spectra of the bimetallic chain compounds were reco…

Self-assembly, metal binding ability, and magnetic properties of dinickel(II) and dicobalt(II) triple mesocates

Two metallacyclic complexes of general formula Na-8[(M2L3)-L-II]center dot xH(2)O [M = Ni (4) and Co (5) with x = 15 (4) and 17 (5)] have been self-assembled in aqueous solution from N,N'-1,3-phenylenebis(oxamic acid) (H4L) and M2+ ions in a ligand/metal molar ratio of 3 : 2 in the presence of NaOH acting as base. X-Ray structural analyses of 4 and 5 show triple-stranded, dinuclear anions of the meso-helicate-type (so-called mesocates) with C-3h molecular symmetry. The two octahedral metal-tris(oxamate) moieties of opposite chiralities (Delta, Lambda form) are connected by three m-phenylene spacers at intermetallic distances of 6.822(2) (4) and 6.868(2) angstrom (5) to give a metallacryptan…

4,2-Ribbon like ferromagnetic cyano-bridged FeIII2NiII chains: a magneto-structural study

The low-spin iron(III) complex AsPh(4)[Fe(III)(bpy)(CN)(4)].CH(3)CN (1) [AsPh(4) = tetraphenylarsonium cation] and the heterobimetallic chains [{Fe(III)(L)(CN)(4)}(2)Ni(II)(H(2)O)(2)].4H(2)O with L = bpy (2) and phen (3) [bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline] have been prepared and their structures determined by X-ray diffraction methods. The structure of 1 consists of mononuclear [Fe(bpy)(CN)(4)](-) anions, tetraphenylarsonium cations and acetonitrile molecules of crystallization. The iron(III) is hexacoordinated with two nitrogen atoms of the bidentate bpy and four carbon atoms of four terminal cyanide groups building a distorted octahedral surrounding around the metal ato…

Photomagnetic effect in a cyanide-bridged mixed-valence {FeII2FeIII2} molecular square

The self-assembly of [Fe(III)(Tp)(CN)(3)](-) and [Fe(II)(bik)(2)(S)(2)](2+) affords the cyanide-bridged mixed valence {Fe(III)(2)Fe(II)(2)}(2+) molecular square, which exhibits a photomagnetic effect under laser light irradiation at low temperature and also shows thermal spin-state conversion near ambient temperature.

Synthesis, crystal structures and magnetic properties of cyanide- and phenolate-bridged [MIIINiII]2tetranuclear complexes (M = Fe and Cr)

The binuclear complex NiII2L(H2O)2(ClO4)2 (1) and the neutral tetranuclear bimetallic compounds [{MIII(phen)(CN)4}2{NiII2L(H2O)2}]·2CH3CN with M = Fe (2) and Cr (3) [H2L = 11,23-dimethyl-3,7,15,19-tetraazatricyclo[19.3.1.19,13]hexacosa-2,7,9,11,13(26),14,19,21(25),22,24-decaene-25,26-diol] have been synthesized and the structures of 2 and 3 determined by single crystal X-ray diffraction. 2 and 3 are isostructural compounds whose structure is made up of centrosymmetric binuclear cations [Ni2(L)(H2O)2]2+ and two peripheral [M(phen)(CN)4]− anions [M = Fe (2) and Cr (3)] acting as monodentate ligands towards the nickel atoms through one of their four cyanide nitrogen atoms. The environment of t…

Design of single chain magnets through cyanide-bearing six-coordinate complexes

Abstract The design and preparation of stable cyanide-bearing six-coordinate complexes of formula [MIII(L)(CN)x](x + l − m)− (M = trivalent transition metal ion and L = polydentate blocking ligand) are summarized here. Their use as ligands towards either fully hydrated metal ions or coordinatively unsaturated preformed species, to afford a wide variety of low-dimensional metal assemblies whose nuclearity, dimensionality and magnetic properties can be tuned, is also reviewed. Special emphasis is put on the appropriate choice of the end-cap ligand L whose denticity determines the number of coordinated cyanide groups in the mononuclear precursors. Among the different new spin topologies obtain…

[Mn2(bipym)(H2O)8]4+and [Fe(bipy)(CN)4]−as building blocks in designing novel bipym- and cyanide-bridged heterobimetallic complexes (bipym = 2,2′-bipyrimidine and bipy = 2,2′-bipyridine)

Two new cyano complexes, K[Fe(bipy)(CN)4]·H2O (1) and (μ-bipym)[Mn(H2O)3{Fe(bipy)(CN)4}]2[Fe(bipy)(CN)4]2·12H2O (2), have been synthesised and their structures determined by single-crystal X-ray diffraction. Complex 1 is made up of mononuclear [Fe(bipy)(CN)4]− anions, potassium cations and water molecules of crystallization. The iron(III) is six-coordinated, being surrounded by two nitrogen atoms of a chelating bipy and four carbon atoms of four cyanide groups [Fe–N and Fe–C 1.991(3)–1.990(3) and 1.958(5)–1.914(5) A, respectively]. Complex 2 consists of centrosymmetric tetranuclear (μ-bipym)[Fe(H2O)3{Fe(bipy)(CN)4}]22+ cations, [Fe(bipy)(CN)4]− anions and water molecules of crystallization.…

Ferromagnetic Coupling between Low- and High-Spin Iron(III) Ions in the Tetranuclear Complex fac-{[FeIII{HB(pz)3}(CN)2(μ-CN)]3FeIII(H2O)3}· 6H2O ([HB(pz)3]- = Hydrotris(1-pyrazolyl)borate)

The novel mononuclear PPh4-fac-[FeIII{HB(pz)3}(CN)3]·H2O (1) [PPh4+= tetraphenylphosphonium cation; (HB(pz)3)- = hydrotris(1-pyrazolyl)borate] and tetranuclear fac-{[FeIII{HB(pz)3}(CN)2(μ-CN)]3FeIII(H2O)3}·6H2O (2) have been prepared and characterized by X-ray diffraction analysis. Crystal data for compound 1:  monoclinic, space group P21/c, a = 9.575(3) A, b = 21.984(4) A, c = 16.863(3) A, β = 100.34(2)°, U = 3486(1) A3, Z = 4. Crystal data for compound 2:  orthorhombic, space group Pnam, a = 14.084(3) A, b = 14.799(4) A, c = 25.725(5) A, U = 5362(2) A3, Z = 4. Compound 1 is a low-spin iron(III) compound with three cyanide ligands in fac arrangement and a tridentate pyrazolylborate ligand …

Dimensionality Switching Through a Thermally Induced Reversible Single-Crystal-to-Single-Crystal Phase Transition in a Cyanide Complex

International audience; The heterometallic hexanuclear cyanide-bridged complex {[Mn(bpym)(H(2)O)](2)[Fe(HB(pz)(3))(CN)(3)](4)} (1), its C(15)N and D(2)O enriched forms {[Mn(bpym)(H(2)O)](2)[Fe(HB(pz)(3))(C(15)N)(3)](4)} (2) and {[Mn(bpym)(D(2)O)](2)[Fe(HB(pz)(3))(CN)(3)](4)} (3), and the hexanuclear derivative complex {[Mn(bpym)(H(2)O)](2)[Fe(B(pz)(4))(CN)(3)](4)}*4H(2)O (4) [bpym = 2,2'-bipyrimidine, HB(pz)(3)(-) = hydrotris(1-pyrazolyl)borate, B(pz)(4)(-) = tetra(1-pyrazolyl)borate] have been synthesized. Their structures have been determined through single-crystal X-ray crystallography at different temperatures. Whereas 3 and 4 maintain a discrete hexanuclear motif during the entire temp…

Cyanide-bridged iron(III)-cobalt(II) double zigzag ferromagnetic chains: two new molecular magnetic nanowires.

and opened the perspective of a potential useof 1D magnetic molecular nanowires for information storage.Even though 1D magnetism is a very active area of research,such dynamic behavior was never detected before since it isnot clear how to fulfill experimentally the requirements of aperfect 1D Ising-type chain. This finding prompted us to lookcarefully at 1D systems containing anisotropic elements,suchas cobalt(ii) and low-spin iron(iii) centers that we synthesizedrecently,

On/Off Photoswitching in a Cyanide-Bridged {Fe2Co2} Magnetic Molecular Square

International audience; A repeatable bidirectional paramagnetic ↔ diamagnetic photomagnetic effect has been observed in the cyanide-bridged Fe-Co square complex {[Fe{B(pz)(4)}(CN)(3)](2)[Co(bik)(2)](2)}(ClO(4))(2)*3H(2)O [B(pz)(4) = tetrapyrazolylborate, bik = bis(1-methylimidazol-2-yl)ketone]. Magnetic measurements and low-temperature single-crystal X-ray diffraction experiments have shown that a complete electron transfer from the diamagnetic Fe(II)-Co(III) state to the paramagnetic Fe(III)-Co(II) metastable state is induced by 808 nm laser light irradiation, whereas the diamagnetic state is recovered in an almost quantitative yield under irradiation at 532 nm.

Synthesis, crystal structure and magnetic properties of a new cyanide-bridged iron(III)–nickel(II) ferromagnetic chain

Abstract The reaction of the iron(III) unit fac-[Fe{HB(pz)3}(CN)3]− [ HB ( pz ) 3 - = hydrotris ( 1 - pyrazolyl ) borate ] as the lithium salt (1) with the nickel(II) complex mer-[Ni(dpt)(H2O)3](ClO4)2 [dpt = dipropylenetriamine] in water affords the heterometallic compound of formula {[FeIII{HB(pz)3}(CN)3]2[NiII(dpt)]}n · 3nH2O (2). The structure of 2 has been determined by X-ray diffraction on single crystals and their magnetic properties have been investigated in the temperature range 1.9–300 K. Compound 2 is a zigzag chain compound with regular alternating bis-monodentate [Fe(1){HB(pz)3}(CN)3]− units and [Ni(dpt)]2+ cations, the six coordination around the nickel atom being achieved by …

[FeIILSCoIIILS]2⇔ [FeIIILSCoIIHS]2 photoinduced conversion in a cyanide-bridged heterobimetallic molecular square

The self-assembly of [Fe(III){B(pz)(4)}(CN)(3)](-) and [Co(II)(bik)(2)(S)(2)](2+) affords the diamagnetic cyanide-bridged [Fe(II)(LS)Co(III)(LS)](2) molecular square which is converted into the corresponding magnetic [Fe(III)(LS)Co(II)(HS)](2) species under light irradiation at relatively low temperatures.

Combining Cyanometalates and Coordination Clusters: An Alternative Synthetic Route toward Original Molecular Materials

International audience; With the discovery of molecules or molecule-based compounds that can display blocked magnetization, magnetic ordering or switchable magnetic bistability, the research efforts devoted to molecular magnetic materials have considerably increased over the past two decades, fully exploiting the advantages of the bottom-up approach. 1-4 This research field focuses on promising properties for potential technological applications such as information storage, quantum computing and spintronics at the molecular scale, but it also provides fundamental insights into original quantum phenomena. 5,6 Coordination chemists have developed efficient synthetic tools for the preparation …

A cyanide and hydroxo-bridged nanocage: a new generation of coordination clusters.

International audience; Combining serendipitously-formed hydroxo-clusters, [CoII3(OH)(piv)4(L)]+ (where L = MeCN or Hpiv), with assembling cyanide building block, [FeIII(Tp)(CN)3]−, has led to an unprecedented architecture where polymetallic cobalt clusters and blocked tris-cyanide iron complexes define the apexes of a unique magnetic cubic nanocage.

An {Fe60} tetrahedral cage: building nanoscopic molecular assemblies through cyanometallate and alkoxo linkers

International audience; A nanoscopic {Fe60} coordination cage (approximately 3 nm) was prepared by the self assembly of a partially blocked tricyanidoferrate(III) complex and tris(alkoxo)-based iron(III) coordination motifs. This cage is a rare example of a mixed cyanido/alkoxo-bridged high nuclearity complex and it exemplifies the great potential of this new synthetic route to generate uncommon molecular architectures using cyanometallates as metalloligands versus alkoxo-based polynuclear entities.

Tuning the Spin Ground State in Heterononanuclear Nickel(II)−Copper(II) Cylinders with a Triangular Metallacyclophane Core

3 páginas, 2 figuras, 1 gráfico.-- et al.

Cover Picture: Cyanide-Bridged Iron(III)–Cobalt(II) Double Zigzag Ferromagnetic Chains: Two New Molecular Magnetic Nanowires (Angew. Chem. Int. Ed. 13/2003)

Inside Cover: Oligo-m-phenyleneoxalamide Copper(II) Mesocates as Electro-Switchable Ferromagnetic Metal-Organic Wires (Chem. Eur. J. 43/2010)

Design of single cyanide-bridged tetranuclear bimetallic rectangles exhibiting ferromagnetic coupling

Abstract The cyanide-bridged tetranuclear bimetallic rectangles ( XPh 4 ) 4 [ Fe 2 III Cu 2 II ( μ - CN ) 4 ( CN ) 8 ( L ) 2 ] · n H 2 O [X = P (1) and As (2); L = bpcam (1) and bpca (2); n = 4 (1) and 0 (2)] have been prepared and their crystal structures were characterized by single crystal X-ray diffraction; 1 exhibits intramolecular ferromagnetic interactions (J1 = +3.7 cm−1 and J2 = +7.0 cm−1, H = - J 1 [ S Fe ( 1 ) · S Cu ( 1 ) + S Fe ( 1 a ) · S Cu ( 1 a ) ] − J 2 [ S Fe ( 1 ) · S Cu ( 1 a ) + S Fe ( 1 a ) · S Cu ( 1 ) ] + D [ S Fe ( 1 ) z 2 + S Fe ( 1 a ) z 2 ] ) leading to a low-lying S = 2 spin state.

Synthesis, Crystal Structures, and Magnetic Properties of a New Family of Heterometallic Cyanide-Bridged FeIII2MII2 (M = Mn, Ni, and Co) Square Complexes

New heterobimetallic tetranuclear complexes of formula [Fe(III){B(pz)(4)}(CN)(2)(μ-CN)Mn(II)(bpy)(2)](2)(ClO(4))(2)·CH(3)CN (1), [Fe(III){HB(pz)(3)}(CN)(2)(μ-CN)Ni(II)(dmphen)(2)](2)(ClO(4))(2)·2CH(3)OH (2a), [Fe(III){B(pz)(4)}(CN)(2)(μ-CN)Ni(II)(dmphen)(2)](2)(ClO(4))(2)·2CH(3)OH (2b), [Fe(III){HB(pz)(3)}(CN)(2)(μ-CN)Co(II)(dmphen)(2)](2)(ClO(4))(2)·2CH(3)OH (3a), and [Fe(III){B(pz)(4)}(CN)(2)(μ-CN)Co(II)(dmphen)(2)](2)(ClO(4))(2)·2CH(3)OH (3b), [HB(pz)(3)(-) = hydrotris(1-pyrazolyl)borate, B(Pz)(4)(-) = tetrakis(1-pyrazolyl)borate, dmphen = 2,9-dimethyl-1,10-phenanthroline, bpy = 2,2'-bipyridine] have been synthesized and structurally and magnetically characterized. Complexes 1-3b have be…

Solid‐State Anion–Guest Encapsulation by Metallosupramolecular Capsules Made from Two Tetranuclear Copper(II) Complexes (Eur. J. Inorg. Chem. 29/2007)

The cover picture shows unique examples of homo- and heterochiral, dimeric metal capsules resulting from the self-assembly of two helical, bowl-shaped tetranuclear copper(II) complexes that encapsulate different anions in the solid state, like pearls in an oyster (shown as the background). This kind of self-assembled, coordination-bonded motifs are a major topic in metallosupramolecular chemistry because of their binding capabilities and associated host–guest chemistry. However, their magnetic properties are largely unexplored, and here we provide one of the rare magnetic studies on these host–guest systems. For more details on the combined structural and magnetic investigations of this cla…

[Fe(bipy)(CN)4]- as a Versatile Building Block for the Design of Heterometallic Systems:  Synthesis, Crystal Structure, and Magnetic Properties of PPh4[FeIII(bipy)(CN)4]·H2O, [{FeIII(bipy)(CN)4}2MII(H2O)4]·4H2O, and [{FeIII(bipy)(CN)4}2ZnII]·2H2O [bipy = 2,2‘-Bipyridine; M = Mn and Zn]

The new cyano complexes of formulas PPh4[FeIII(bipy)(CN)4]·H2O (1), [{FeIII(bipy)(CN)4}2MII(H2O)4]·4H2O with M = Mn (2) and Zn (3), and [{FeIII(bipy)(CN)4}2ZnII]·2H2O (4) [bipy = 2,2‘-bipyridine and PPh4 = tetraphenylphosphonium cation] have been synthesized and structurally characterized. The structure of complex 1 is made up of mononuclear [Fe(bipy)(CN)4]- anions, tetraphenyphosphonium cations, and water molecules of crystallization. The iron(III) is hexacoordinated with two nitrogen atoms of a chelating bipy and four carbon atoms of four terminal cyanide groups, building a distorted octahedron around the metal atom. The structure of complexes 2 and 3 consists of neutral centrosymmetric […

[Criii(L)(CN)4]−: a new building block in designing cyanide-bridged 4,2-ribbon-like chains {[Criii(L)(CN)4]2Mn(H2O)2}·nH2O [L = 2-aminomethylpyridine (n = 6) and 1,10-phenanthroline (n = 4)]

The preparation, X-ray crystallography and magnetic study of compounds PPh4[Cr(ampy)(CN)4]·H2O (1), PPh4[Cr(phen)(CN)4]·H2O·CH3OH (2), {[Cr(ampy)(CN)4]2Mn(H2O)2}·6H2O (3) and {[Cr(phen)(CN)4]2Mn(H2O)2}·4H2O (4), with PPh4+ = tetraphenylphosphonium cation, ampy = 2-aminomethylpyridine and phen = 1,10-phenanthroline, are reported here. 1 and 2 are mononuclear complexes whereas 3 and 4 are 4,2-ribbon-like bimetallic chains. The magnetic properties of 1–4 were investigated in the temperature range 1.9–300 K. A quasi Curie law behaviour for a magnetically isolated spin quartet is observed for 1 and 2. Compounds 3 and 4 are ferrimagnetic CrIII2MnII chains, which exhibit a metamagnetic behaviour, …

Ligand design for multidimensional magnetic materials: a metallosupramolecular perspective.

The aim and scope of this review is to show the general validity of the ‘complex-as-ligand’ approach for the rational design of metallosupramolecular assemblies of increasing structural and magnetic complexity. This is illustrated herein on the basis of our recent studies on oxamato complexes with transition metal ions looking for the limits of the research avenue opened by Kahn's pioneering research twenty years ago. The use as building blocks of mono-, di- and trinuclear metal complexes with a novel family of aromatic polyoxamato ligands allowed us to move further in the coordination chemistry-based approach to high-nuclearity coordination compounds and high-dimensionality coordination po…

Charge transfer salts containing a paramagnetic cyano-complex and iodine substituted organic donor involving –I(donor)···N(anion)-interactions

Abstract The preparation, crystal structures, EHT band calculation and optical properties of two new charge transfer salts, namely (DIET)2[Fe(bpca)(CN)3] (1) and (DIEDO)2[Fe(bpca)(CN)3] (2), where bpca = bis(2-pyridylcarbonyl)amide anion, DIET = diiodoethylenedithotetrathiavalene and DIEDO = diiodoethylenedioxotetrathiavalene are reported. The magnetic properties of 2 and those of the low-spin iron(III) precursor of formula (PPh4)[Fe(bpca)(CN)3]·H2O (3) were also investigated in the temperature range 1.9–205 K. Crystal data; (1): monoclinic P21, a = 8.8238(2)A, b = 13.2891(3) A, c = 18.5042(5) A, β = 91.115(1)°, Z = 2, R = 0.0710 for 7021 independent reflections with I > 2 σ(I) and (2): Mon…

[Cr(AA)(C2O4)2]− and [Cu(bpca)]+ as building blocks in designing new oxalato-bridged CrIIICuII compounds [AA=2,2′-bipyridine and 1,10-phenanthroline; bpca=bis(2-pyridylcarbonyl)amide anion]

Abstract The monouclear complex PPh4[Cr(bipy)(ox)2]·H2O (1) and the heterodinuclear compounds [Cu(bpca)(H2O)Cr(bipy)(ox)2]·2.5H2O (2) and [Cu(bpca)(H2O)Cr(phen)(ox)2]·2H2O (3) [PPh4+=tetraphenylphosphonium cation, bpca=bis(2-pyridylcarbonyl)amide anion, ox=oxalate dianion, bipy=2,2′-bipyridine and phen=1,10-phenanthroline] have been synthesized and characterized by single-crystal X-ray diffraction. Discrete [Cr(bipy)(ox)2]− mononuclear anions and tetraphenylphosphonium cations are present in 1 whereas the structures of 2 and 3 are made up neutral oxalato-bridged bimetallic CrIIICuII units. The chromium environment is distorted octahedral in the three complexes: two nitrogen atoms from a bi…

A Metallacryptand-Based Manganese(II)–Cobalt(II) Ferrimagnet with a Three-Dimensional Honeycomb Open-Framework Architecture

Cyanide-bridged Fe(III)–Co(II) bis double zigzag chains with a slow relaxation of the magnetisation

Reaction of [FeIII(bipy)(CN)4]¯ with fully solvated MII cations [M = Co (1) and Mn (2)] produces the isostructural bis double zigzag chains [[FeIII(bipy)(CN)4]2MII(H2O)]·MeCN·1/2H2O; 1 exhibits intrachain ferromagnetic and interchain antiferromagnetic couplings, slow magnetic relaxation and hysteresis effects. Luminita Marilena, Toma, Luminita.Toma@uv.es ; Lescouezec, Alain Francois Rodri, Alain.Lescouezec@uv.es ; Lloret Pastor, Francisco, Francisco.Lloret@uv.es ; Julve Olcina, Miguel, Miguel.Julve@uv.es

CCDC 951875: Experimental Crystal Structure Determination

Related Article: Abhishake Mondal, Pierre-Igor Dassié, Lise-Marie Chamoreau, Yves Journaux, Miguel Julve, Laurent Lisnard, and Rodrigue Lescouëzec|2013|Cryst.Growth Des.|13|4190|doi:10.1021/cg401117u