Journal ArticleDOI
Two-Step versus One-Step Spin Transitions in Iron(II) 1D Chain Compounds
Wolfgang Bauer,Wolfgang Scherer,Sandra Altmannshofer,Sandra Altmannshofer,Birgit Weber,Birgit Weber +5 more
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In this paper, 11 iron(II) 1D coordination polymers with the general formula [FeLeq(Lax)]·solvent were synthesized and characterised, where Leq = (E,E)-{diethyl 2,2′-[1,2-phenylenebis(iminomethylidyne)]bis(3-oxobutanato) (2-)-N,N′,O3-O3, O3′} (L1) and solvent = MeOH, EtOH and toluene (TAbstract:
Eleven iron(II) 1D coordination polymers with the general formula [FeLeq(Lax)]·solvent were synthesised and characterised, where Leq = (E,E)-{diethyl 2,2′-[1,2-phenylenebis(iminomethylidyne)]bis(3-oxobutanato) (2-)-N,N′,O3,O3′} (L1) and {[3,3′]-[1,2-phenylenebis(iminomethylidyne)]bis(2,4-pentane-dionato)(2-)-N,N′,O2,O2′} (L2); Lax = 4,4′-bipyridine (bipy), 1,2-bis(4-pyridyl)ethane (bpea) and 1,3-bis(4-pyridyl)propane (bppa) and solvent = MeOH, EtOH and toluene (Tol). [FeL1(bpea)]·MeOH (3·MeOH) shows an abrupt one-step spin crossover with thermal hysteresis(27 K) and [FeL2(bppa)]·MeOH (2·MeOH), [FeL2(bpea)] (4), [FeL2(bpea)]·0.25MeOH (4·0.25MeOH) and [FeL1(bipy)]·MeOH (5·MeOH) show a two-step spin transition with an IP at γHS ≈ 0.5 (IP is intermediate plateau and γHS is high-spin mol fraction) and up to 50 K wide hysteresis loops (5·MeOH). [FeL1(bppa)] (1), [FeL2(bppa)]·EtOH (2·EtOH) and [FeL1(bpea)]·1.5Tol (3·1.5Tol) show an abrupt incomplete spin transition that stops at γHS ≈ 0.5; for [FeL1(bppa)]·0.25MeOH (1·0.25MeOH) and [FeL1(bpea)] (3), the spin transition is gradual and incomplete. The X-ray crystal structures of six complexes were determined (1, 2·MeOH, 3·MeOH, 3·1.5Tol, 4·0.25MeOH and 5·MeOH). In the case of 4·0.25MeOH, the crystal structures for the HS and LS states were dertermined; for compounds 1, 2·MeOH and 3·1.5Tol, the crystal structure of the HS and the IP state was investigated. For all complexes, the iron(II) centre is located in a distorted octahedral coordination sphere. Each axially coordinated ligand “connects” two iron(II) centres, which results in the formation of extended 1D chains with varying structures from linear (bipy) over steplike (bpea) to zigzag (bppa). Analysis of the intermolecular interactions reveals that the hysteresis width depends on both the stiffness of the axial ligand and the number of intermolecular contacts, while zigzag chains support stepwise spin transitions.read more
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Spin state switching in iron coordination compounds
TL;DR: The article deals with coordination compounds of iron(II) that may exhibit thermally induced spin transition, known as spin crossover, depending on the nature of the coordinating ligand sphere, and the variety of physical techniques usually applied for their characterization.
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Triazole-based one-dimensional spin-crossover coordination polymers.
TL;DR: This Minireview provides the first complete overview of one-dimensional coordination Fe(II) polymers and their most recent developments.
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Spin-crossover Compounds with Wide Thermal Hysteresis
TL;DR: In this paper, a survey of spin-crossover compounds showing wide thermal hysteresis is presented, and the factors underlying these properties are discussed, such as large structural rearrangements during th...
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Large thermal hysteresis for iron(II) spin crossover complexes with N-(pyrid-4-yl)isonicotinamide.
TL;DR: The results show that the pina ligand was used successfully in a crystal-engineering-like approach to generate 1D coordination polymers and improve their spin crossover properties.
Journal ArticleDOI
Remarkably high-temperature spin transition exhibited by new 2D metal–organic frameworks
Xin Bao,Peng-Hu Guo,Wei Liu,Jiri Tucek,Wei-Xiong Zhang,Ji-Dong Leng,Xiao-Ming Chen,Il'ya A. Gural'skiy,Lionel Salmon,Azzedine Bousseksou,Ming-Liang Tong +10 more
TL;DR: In this article, the two-step spin crossover properties at remarkably high temperatures, namely Tc1 = 329 K, Tc2 = 501 K for 1 and Tc3 = 520 K for 2, were reported.
References
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Journal ArticleDOI
ORTEP-3 for Windows - a version of ORTEP-III with a Graphical User Interface (GUI)
TL;DR: L Lists of software presented and~or reviewed in the Journal of Applied Crystallography are available on the World Wide Web at the above address, together with information about the availability of the software where this is known.
Journal ArticleDOI
SIR97: a new tool for crystal structure determination and refinement
Angela Altomare,Maria Cristina Burla,Mercedes Camalli,Giovanni Luca Cascarano,Carmelo Giacovazzo,Antonietta Guagliardi,Anna Moliterni,Giampiero Polidori,Riccardo Spagna +8 more
TL;DR: SIR97 is the integration of two programs, SIR92 and CAOS, the first devoted to the solution of crystal structures by direct methods, the second to refinement via least-squares–Fourier procedures.
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Spin-Transition Polymers: From Molecular Materials Toward Memory Devices
O. Kahn,C. Jay Martinez +1 more
TL;DR: In this article, the transition temperature of transition metal compounds can be fine tuned using an approach based on the concept of a molecular alloy, and it is possible to design a compound for which room temperature falls in the middle of the thermal hysteresis loop.
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Thermal and Optical Switching of Iron(II) Complexes
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Thermal, pressure and light switchable spin-crossover materials
TL;DR: The different approaches currently being explored in order to achieve multifunctionality in SCO materials are discussed.