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Jia S, Shang M, Jin S, Zhu X, Cai Y, Li D. Electron transfer coupled spin transition in cyano-bridged mixed-valence {FeIII2FeII2} molecular squares. Dalton Trans 2024; 53:2807-2814. [PMID: 38230412 DOI: 10.1039/d3dt03208f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
The research on electron transfer coupled spin transition regulating the valence state and spin state transition of metal ions is promising and challenging. Herein, we report a cyano-bridged {FeIII2FeII2} molecular square complex, {[Fe(Tp)(CN)3]2 [Fe(bnbpen)]2}(ClO4)2·8CH3OH (1·8CH3OH, bnbpen = N,N'-bis-(2-naphthylmethyl)-N,N'-bis(2-picolayl)-ethylenediamine), and its free of solvents form (1). Combined single-crystal X-ray diffraction, temperature-dependent infrared (IR) spectra, magnetic measurements, and Mössbauer spectra reveal that 1·8CH3OH and 1 exhibit reversible one-step and two-step electron transfer coupled spin transition (ETCST) with temperature change, between the low-temperature state {FeII,LS(μ-CN)FeIII,LS}2 (LS = low spin, HS = high spin) and the high-temperature state {FeIII,LS(μ-CN)FeII,HS}2, respectively.
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Affiliation(s)
- Shuwen Jia
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Mengjia Shang
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Sai Jin
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Xinrui Zhu
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Yuanyuan Cai
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Dongfeng Li
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
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2
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Fischer TE, Janetzki JT, M Zahir FZ, Gable RW, Starikova AA, Boskovic C. Tuning valence tautomerism in a family of dinuclear cobalt complexes incorporating a conjugated bridging bis(dioxolene) ligand with weak communication. Dalton Trans 2024. [PMID: 38236053 DOI: 10.1039/d3dt04162j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Valence tautomerism (VT) involves the stimulated reversible intramolecular electron transfer between a redox-active metal and ligand. Dinuclear cobalt complexes bridged by bis(dioxolene) ligands can undergo thermally-induced VT with access to {CoIII-cat-cat-CoIII}, {CoIII-cat-SQ-CoII} and {CoII-SQ-SQ-CoII} states (cat2- = catecholate, SQ˙- = semiquinonate, CoIII refers to low spin CoIII, CoII refers to high spin CoII). The resulting potential for two-step VT interconversions offers increased functionality over mononuclear examples. In this study, the bis(dioxolene) ligand 3,3',4,4'-tetrahydroxy-5,5'-dimethoxy-benzaldazine (thMH4) was paired with Mentpa (tpa = tris(2-pyridylmethyl)amine, n = 0-3 corresponds to methylation at 6-position of the pyridine rings) to afford [{Co(Mentpa)}2(thM)](PF6)2 (1a, n = 0; 2a, n = 2; 3a, n = 3). Structural, magnetic susceptibility and spectroscopic data show that 1a and 3a remain in the temperature invariant {CoIII-cat-cat-CoIII} and {CoII-SQ-SQ-CoII} forms in the solid state, respectively. In contrast, 2a exhibits incomplete thermally-induced VT between these two tautomeric forms via the mixed {CoIII-cat-SQ-CoII} tautomer. In solution, room temperature electronic absorption spectra are consistent with the assignments from the solid-state, with VT observed only for 2a. From electrochemistry, the proximity of the two 1e--processes for the thMn- ligand indicates weak electronic communication between the two dioxolene units, supporting the potential for a two-step VT interconversion in thMn- containing complexes. Comparison of the redox potentials of the Co and thMn- processes suggests that only 2a has these processes in sufficient proximity to afford the thermally-induced VT observed experimentally. Density functional theory calculations are consistent with the prerequisite energy ordering for a two-step transition for 2a, and temperature invariant {CoIII-cat-cat-CoIII} and {CoII-SQ-SQ-CoII} states for 1a and 3a, respectively. This work presents the third example, and the first formally conjugated example, of a bridging bis(dioxolene) ligand that can afford two-step VT in a Co complex, suggesting new possibilities towards applications based on multistep switching.
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Affiliation(s)
- Tristan E Fischer
- School of Chemistry, University of Melbourne, Parkville, 3010 Victoria, Australia.
| | - Jett T Janetzki
- School of Chemistry, University of Melbourne, Parkville, 3010 Victoria, Australia.
| | - F Zahra M Zahir
- School of Chemistry, University of Melbourne, Parkville, 3010 Victoria, Australia.
| | - Robert W Gable
- School of Chemistry, University of Melbourne, Parkville, 3010 Victoria, Australia.
| | - Alyona A Starikova
- Institute of Physical and Organic Chemistry, Southern Federal University, 344090, Rostov-on-Don, Russian Federation
| | - Colette Boskovic
- School of Chemistry, University of Melbourne, Parkville, 3010 Victoria, Australia.
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3
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Kaushik K, Mehta S, Das M, Ghosh S, Kamilya S, Mondal A. Stimuli-responsive magnetic materials: impact of spin and electronic modulation. Chem Commun (Camb) 2023; 59:13107-13124. [PMID: 37846652 DOI: 10.1039/d3cc04268e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Addressing molecular bistability as a function of external stimuli, especially in spin-crossover (SCO) and metal-to-metal electron transfer (MMET) systems, has seen a surge of interest in the field of molecule-based magnetic materials due to their enormous potential in various technological applications such as molecular spintronics, memory and electronic devices, switches, sensors, and many more. The fine-tuning of molecular components allow the design and synthesis of materials with tailored properties for these vast applications. In this Feature Article, we discuss a part of our research work into this broad topic, pertaining to the recent discoveries in the field of switchable molecular magnetic materials based on SCO and MMET systems, along with some historical background of the area and related accomplishments made in recent years.
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Affiliation(s)
- Krishna Kaushik
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
| | - Mayurika Das
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
| | - Sounak Ghosh
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
| | - Sujit Kamilya
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India.
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4
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Jia S, Zhu X, Li D. Observation of protonation-induced intra-molecular metal-to-metal charge transfer in cyano-bridged [Fe-CN-Mn/Ni] dinuclear complexes. Dalton Trans 2023; 52:15009-15016. [PMID: 37811745 DOI: 10.1039/d3dt02200e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
A key challenge in the design of magnetic molecules with intramolecular charge transfer behavior is to obtain reversible magnetic bistability triggered by external stimuli. Here, we show that two dinuclear metal complexes, [(bbp)Fe(CN)3Mn(Py5Me2)]·2.5CH3OH (4) and [(bbp)Fe(CN)3Ni(Py5Me2)]·2.5CH3OH (5) (Py5Me2 = 2,6-bis(1,1-di(pyridine-2-yl)ethyl)pyridine, H2bbp = 2,6-bis(benzimidazole-2-yl)pyridine), were self-assembly synthesized by (Bu4N)2[(bbp)FeIII(CN)3] and [Mn(Py5Me2)(OH2)](ClO4)2 or [Ni(Py5Me2)(OH2)](ClO4)2, respectively. Complexes 4 and 5 exhibited intramolecular metal-to-metal charge transfer with the addition of acids or bases in solution by UV-visible spectrophotometric measurements and electrochemistry studies, and concomitant switching of the {FeIII(μ-CN)MnII/NiII} state to the {FeII(μ-CN)MnIII/NiIII} state.
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Affiliation(s)
- Shuwen Jia
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Xinrui Zhu
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
| | - Dongfeng Li
- Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, 430079 Wuhan, P. R. China.
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5
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Gajecki L, Sawicka B, Berg DJ, Oliver AG. Synthesis and Magnetic Studies of Two Neutral, Bis-Ligand Fe(II) Complexes Containing Carbazole- Bis(tetrazole) Ligands. Inorg Chem 2023. [PMID: 37478316 DOI: 10.1021/acs.inorgchem.3c01167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Previously reported carbazole-bis(tetrazole) (CzTR) ligands (where R = iPr and CH2-2,4,6-C6H2Me3) were used to synthesize air-stable, six-coordinate, octahedral bis-ligand Fe(II) complexes (CzTR)2Fe. The synthesis and characterization of these complexes using 1H nuclear magnetic resonance (NMR), X-ray crystallography, Mössbauer spectroscopy, and density functional theory (DFT) calculations are reported. Analysis of the magnetic properties revealed that the isopropyl derivative displays thermally induced spin crossover (SCO) over a temperature range of 150-350 K. This transition appears as an abrupt two-step transition in the solid state but simplifies to a smooth one-step transition in solution. The two-step transition in the solid state has been postulated to be due to lattice and solvation effects. In contrast, the slightly bulkier substituted CH2-2,4,6-C6H2Me3 (CH2Mes) Fe complex displays dramatically different magnetic behavior with no SCO and magnetic data suggesting low-spin Fe(II) with a possible TIP contribution. DFT calculations support the postulate that the change in magnetic behavior is primarily due to the nature of the ligand substituents.
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Affiliation(s)
- Leah Gajecki
- Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada V8W 3V6
| | - Barbara Sawicka
- Department of Mechanical Engineering, University of Victoria, P.O. Box 1700 STN CSC, Victoria, British Columbia, Canada V8W 2Y2
| | - David J Berg
- Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada V8W 3V6
| | - Allen G Oliver
- Department of Chemistry & Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556, United States
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Díaz-Torres R, Chastanet G, Collet E, Trzop E, Harding P, Harding DJ. Bidirectional photoswitchability in an iron(iii) spin crossover complex: symmetry-breaking and solvent effects. Chem Sci 2023; 14:7185-7191. [PMID: 37416698 PMCID: PMC10321481 DOI: 10.1039/d3sc01495a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/31/2023] [Indexed: 07/08/2023] Open
Abstract
The impact of solvent on spin crossover (SCO) behaviour is reported in two solvates [Fe(qsal-I)2]NO3·2ROH (qsal-I = 4-iodo-2-[(8-quinolylimino)methyl]phenolate; R = Me 1 or Et 2) which undergo abrupt and gradual SCO, respectively. A symmetry-breaking phase transition due to spin-state ordering from a [HS] to [HS-LS] state occurs at 210 K in 1, while T1/2 = 250 K for the EtOH solvate, where complete SCO occurs. The MeOH solvate exhibits LIESST and reverse-LIESST from the [HS-LS] state, revealing a hidden [LS] state. Moreover, photocrystallographic studies on 1 at 10 K reveal re-entrant photoinduced phase transitions to a high symmetry [HS] phase when irradiated at 980 nm or a high symmetry [LS] phase after irradiation at 660 nm. This study represents the first example of bidirectional photoswitchability and subsequent symmetry-breaking from a [HS-LS] state in an iron(iii) SCO material.
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Affiliation(s)
- Raúl Díaz-Torres
- Thammasat University Research Unit in Multifunctional Crystalline Materials and Applications (TU-MCMA), Faculty of Science and Technology, Thammasat University Pathum Thani 12121 Thailand
| | - Guillaume Chastanet
- Université de Bordeaux, ICMCB 87 Avenue du Dr A. Schweitzer Pessac F-33608 France
| | - Eric Collet
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251 F-35000 Rennes France
| | - Elzbieta Trzop
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251 F-35000 Rennes France
| | - Phimphaka Harding
- School of Chemistry, Institute of Science, Suranaree University of Technology Nakhon Ratchasima 30000 Thailand
| | - David J Harding
- School of Chemistry, Institute of Science, Suranaree University of Technology Nakhon Ratchasima 30000 Thailand
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Shi L, Kobylarczyk J, Dziedzic-Kocurek K, Stanek JJ, Sieklucka B, Podgajny R. Site Selectivity for the Spin States and Spin Crossover in Undecanuclear Heterometallic Cyanido-Bridged Clusters. Inorg Chem 2023; 62:7032-7044. [PMID: 37120844 PMCID: PMC10170501 DOI: 10.1021/acs.inorgchem.3c00325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Polynuclear molecular clusters offer an opportunity to design new hierarchical switchable materials with collective properties, based on variation of the chemical composition, size, shapes, and overall building blocks organization. In this study, we rationally designed and constructed an unprecedented series of cyanido-bridged nanoclusters realizing new undecanuclear topology: FeII[FeII(bzbpen)]6[WV(CN)8]2[WIV(CN)8]2·18MeOH (1), NaI[CoII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·28MeOH (2), NaI[NiII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·27MeOH (3), and CoII[CoII(R/S-pabh)2]6[WV(CN)8]2[WIV(CN)8]2·26MeOH [4R and 4S; bzbpen = N1,N2-dibenzyl-N1,N2-bis(pyridin-2-ylmethyl)ethane-1,2-diamine; R/S-pabh = (R/S)-N-(1-naphthyl)-1-(pyridin-2-yl)methanimine], of size up to 11 nm3, ca. 2.0 × 2.2 × 2.5 nm (1-3) and ca. 1.4 × 2.5 × 2.5 nm (4). 1, 2, and 4 exhibit site selectivity for the spin states and spin transition related to the structural speciation based on subtle exogenous and endogenous effects imposed on similar but distinguishable 3d metal-ion-coordination moieties. 1 exhibits a mid-temperature-range spin-crossover (SCO) behavior that is more advanced than the previously reported SCO clusters based on octacyanidometallates and an onset of SCO behavior close to room temperature. The latter feature is also present in 2 and 4, which suggests the emergence of CoII-centered SCO not observed in previous bimetallic cyanido-bridged CoII-WV/IV systems. In addition, reversible switching of the SCO behavior in 1 via a single-crystal-to-single-crystal transformation during desolvation was also documented.
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Affiliation(s)
- Le Shi
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland
- Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Jedrzej Kobylarczyk
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland
- Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Kraków, Poland
| | - Katarzyna Dziedzic-Kocurek
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Jan J Stanek
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Krakow, Poland
| | - Barbara Sieklucka
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland
| | - Robert Podgajny
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland
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8
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Kamilya S, Mehta S, Semwal M, Lescouëzec R, Li Y, Pechousek J, Reddy VR, Rivière E, Rouzières M, Mondal A. ON/OFF Photo(switching) along with Reversible Spin-State Change and Single-Crystal-to-Single-Crystal Transformation in a Mixed-Valence Fe(II)Fe(III) Molecular System. Inorg Chem 2023. [PMID: 36867089 DOI: 10.1021/acs.inorgchem.2c03972] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
A mixed-valence Fe(II)Fe(III) molecular system, {[Fe(pzTp)(CN)3]2[Fe(bik)2]2}·[Fe(pzTp)(CN)3]2·4MeOH (1·4MeOH) (bik = bis-(1-methylimidazolyl)-2-methanone, pzTp = tetrakis(pyrazolyl)borate), exhibits single-crystal-to-single-crystal (SC-SC) transformation while increasing the temperature and is converted into {[Fe(pzTp)(CN)3]2[Fe(bik)2]2}·[Fe(pzTp)(CN)3]2 (1). Both complexes exhibit thermo-induced spin-state switching behavior along with reversible SC-SC transformation, where the low-temperature [FeIIILSFeIILS]2 phase transforms into a high-temperature [FeIIILSFeIIHS]2 phase. 1·4MeOH exhibits an abrupt spin-state switching with T1/2 at 355 K, whereas 1 undergoes a gradual and reversible spin-state switching with a lower T1/2 at 338 K. Astonishingly, 1 exhibits ON/OFF photo-induced spin-state switching with TLIESST = 67 K, whereas 1·4MeOH does not show such an effect.
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Affiliation(s)
- Sujit Kamilya
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C. V. Raman Road, Bangalore 560012, India
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C. V. Raman Road, Bangalore 560012, India
| | - Mohini Semwal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C. V. Raman Road, Bangalore 560012, India
| | - Rodrigue Lescouëzec
- Sorbonne Université, Institut Parisien de Chimie Moléculaire, UMR CNRS 8232, 4 place Jussieu, Paris 750005, France
| | - Yanling Li
- Sorbonne Université, Institut Parisien de Chimie Moléculaire, UMR CNRS 8232, 4 place Jussieu, Paris 750005, France
| | - Jiri Pechousek
- Department of Experimental Physics, Palacký University Olomouc, 17, listopadu 1192/12, 771 46 Olomouc, Czech Republic
| | - Varimalla R Reddy
- UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India
| | - Eric Rivière
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, UMR 8182, bât. 420, Université Paris-Sud, 11 rue George Clémenceau, 91405 Orsay Cedex, France
| | - Mathieu Rouzières
- Centre de Recherche Paul Pascal, UMR 5031, Université de Bordeaux, CNRS, 33600 Pessac, France
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C. V. Raman Road, Bangalore 560012, India
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9
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Kulmaczewski R, Armstrong IT, Catchpole P, Ratcliffe ESJ, Vasili HB, Warriner SL, Cespedes O, Halcrow MA. Di-Iron(II) [2+2] Helicates of Bis-(Dipyrazolylpyridine) Ligands: The Influence of the Ligand Linker Group on Spin State Properties. Chemistry 2023; 29:e202202578. [PMID: 36382594 PMCID: PMC10108139 DOI: 10.1002/chem.202202578] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/18/2022]
Abstract
Four bis[2-{pyrazol-1-yl}-6-{pyrazol-3-yl}pyridine] ligands have been synthesized, with butane-1,4-diyl (L1 ), pyrid-2,6-diyl (L2 ), benzene-1,2-dimethylenyl (L3 ) and propane-1,3-diyl (L4 ) linkers between the tridentate metal-binding domains. L1 and L2 form [Fe2 (μ-L)2 ]X4 (X- =BF4 - or ClO4 - ) helicate complexes when treated with the appropriate iron(II) precursor. Solvate crystals of [Fe2 (μ-L1 )2 ][BF4 ]4 exhibit three different helicate conformations, which differ in the torsions of their butanediyl linker groups. The solvates exhibit gradual thermal spin-crossover, with examples of stepwise switching and partial spin-crossover to a low-temperature mixed-spin form. Salts of [Fe2 (μ-L2 )2 ]4+ are high-spin, which reflects their highly twisted iron coordination geometry. The composition and dynamics of assembly structures formed by iron(II) with L1 -L3 vary with the ligand linker group, by mass spectrometry and 1 H NMR spectroscopy. Gas-phase DFT calculations imply the butanediyl linker conformation in [Fe2 (μ-L1 )2 ]4+ influences its spin state properties, but show anomalies attributed to intramolecular electrostatic repulsion between the iron atoms.
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Affiliation(s)
- Rafal Kulmaczewski
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Isaac T Armstrong
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Pip Catchpole
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.,Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK
| | - Emily S J Ratcliffe
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Hari Babu Vasili
- School of Physics and Astronomy W. H. Bragg Building, University of Leeds, Leeds, LS2 9JT, UK
| | - Stuart L Warriner
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Oscar Cespedes
- School of Physics and Astronomy W. H. Bragg Building, University of Leeds, Leeds, LS2 9JT, UK
| | - Malcolm A Halcrow
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
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10
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Highly Porous Cyanometallic Spin-Crossover Frameworks Employing Pyridazino[4,5-d]pyridazine Bridge. INORGANICS 2022. [DOI: 10.3390/inorganics10110195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Single crystals of two spin-crossover (SCO) cyanometallic coordination polymers based on the pyridazino[4,5-d]pyridazine ligand (pp) of the composition [Fe(pp)M(CN)4]∙G (where M = Pd, Pt; G = guest molecules) were obtained by a slow diffusion technique. A single-crystal X-ray analysis showed that both compounds adopted the structure of porous 3D frameworks, consisting of heterometallic cyano-bridged layers and interlayer pillar pp ligands, with a total solvent accessible volume of ca. 160 Å3 per iron(II) ion (about 37% of the unit cell volume). These frameworks displayed hysteretic SCO behaviour with T1/2 of 150/190 K (heating/cooling) for Pd complex and 135/170 K (heating/cooling) for Pt complex, which was confirmed by variable-temperature SCXRD experiments. This research shows the perspective of using pp ligand for building porous MOFs with spin transitions.
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11
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Hiiuk VM, Shylin SI, Barakhtii DD, Korytko DM, Kotsyubynsky VO, Rotaru A, Shova S, Gural'skiy IA. Two-Step Spin Crossover in Hofmann-Type Coordination Polymers [Fe(2-phenylpyrazine) 2{M(CN) 2} 2] (M = Ag, Au). Inorg Chem 2022; 61:2093-2104. [PMID: 35029111 DOI: 10.1021/acs.inorgchem.1c03302] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two 2D Hofmann-type complexes of the composition [Fe(Phpz)2{M(CN)2}2] (where Phpz = 2-phenylpyrazine; M = Ag, Au) have been synthesized, and their spin-crossover (SCO) behavior has been thoroughly characterized. Single-crystal X-ray analysis reveals that these complexes contain a crystallographically unique Fe(II) center surrounded by two axial Phpz ligands and four equatorial cyanide [M(CN)2]- bridges. It is shown that, using of a ligand with two aromatic rings, an advanced system of weak supramolecular interactions (metal-metal, C-H···M, and π···π stacking contacts) is realized. This ensures additional stabilization of the structures and the absence of solvent-accessible voids due to dense packing. Both complexes are characterized by a highly reproducible two-step SCO behavior, as revealed by different techniques (superconducting quantum interference device magnetometry, optical microscopy, etc.). Research shows the exceptional role of the presence of various supramolecular interactions in the structure and the influence of the bulky substituent in the ligand on SCO behavior. Moreover, the perspective of substituted pyrazines for the design of new switchable materials is supported by this work.
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Affiliation(s)
- Volodymyr M Hiiuk
- Department of Chemistry, Taras Shevchenko National University of Kyiv, 64 Volodymyrska Street, 01601 Kyiv, Ukraine.,Faculty of Natural Sciences, National University of Kyiv-Mohyla Academy, 2 Skovorody Street, 04070 Kyiv, Ukraine
| | - Sergii I Shylin
- Ångström Laboratory, Department of Chemistry, Uppsala University, 75120 Uppsala, Sweden
| | - Diana D Barakhtii
- Department of Chemistry, Taras Shevchenko National University of Kyiv, 64 Volodymyrska Street, 01601 Kyiv, Ukraine
| | - Dmytro M Korytko
- Department of Chemistry, Taras Shevchenko National University of Kyiv, 64 Volodymyrska Street, 01601 Kyiv, Ukraine
| | - Volodymyr O Kotsyubynsky
- Department of Material Science and New Technology, Vasyl Stefanyk Precarpathian National University, 57 Shevchenko Street, 76018 Ivano-Frankivsk, Ukraine
| | - Aurelian Rotaru
- Faculty of Electrical Engineering and Computer Science & Research Center MANSiD, Stefan cel Mare University, 13 Universitatii Street, 720229 Suceava, Romania
| | - Sergiu Shova
- Ningbo University of Technology, No. 201, Fenghua Road, Ningbo City, Zhejiang 315211, China.,"Petru Poni" Institute of Macromolecular Chemistry, 41A Aleea Gr. Ghica Voda, 700487 Iasi, Romania
| | - Il'ya A Gural'skiy
- Department of Chemistry, Taras Shevchenko National University of Kyiv, 64 Volodymyrska Street, 01601 Kyiv, Ukraine
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12
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Jia S, Fan L, Zheng CY, Jin S, Li D. Mixed-valence {FeII2FeIII4} hexanuclear complexes with thermally induced Fe(III) spin crossover behavior. Dalton Trans 2022; 51:12968-12974. [DOI: 10.1039/d2dt02041f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cyano-bridged mixed-valence {Fe6} hexanuclear complexes {[Tp4-MeFeII(CN)3]2[FeIII(Tpa)]2[FeIII(OR)(Tpa)]2}·6ClO4·S {Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate, Tpa = Tris(2-pyridylmethyl)amine; R = -CH3 S = 8MeOH 1, R = -C2H5 S = 6EtOH 2 } have been obtained...
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13
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You M, Nguyen GT, Shao D, Wang T, Chang X, Ungur L, Zhang YZ. Manipulating the spin crossover behaviour in a series of cyanide-bridged {FeIII2FeII2} molecular squares through NCE- co-ligands. Dalton Trans 2022; 51:5596-5602. [DOI: 10.1039/d2dt00058j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Manipulating the transition temperature (T1/2) of spin-crossover (SCO) complexes capable of fulfilling practical criteria through different synthetic strategies is one of the main focuses in the field of molecular magnetism....
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14
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Chen ZY, Cheng Y, Liu Q, Deng YF, Zhang YZ. Polyoxometalate-Assisted Assembly of Pearl-Chain-Like Cyanide-Bridged Single-Chain Magnets. Inorg Chem 2021; 61:931-938. [PMID: 34962120 DOI: 10.1021/acs.inorgchem.1c02922] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The introduction of Keggin-type POMs of [PMo12O40]3- or [SiW12O40]4- as counteranions into the FeIII-MII cyanometalate system afforded three chain complexes: [(Tp*)Fe(CN)3Ni(DMF)4]2{[(Tp*)Fe(CN)3Ni(DMF)3(H2O)]2Ni(DMF)4}[PMo12O40]2·14DMF (1, Tp*= hydridotris(3,5-dimethylpyrazol-1-yl)borate) and {[(Tp*)Fe(CN)3M(DMF)3(H2O)]2M(DMF)4}[SiW12O40]·3DMF (2, M = NiII; 3, M = CoII). Complex 1 contains both discrete cationic [Fe2Ni2]2+ squares and less-studied {Fe2Ni3}n pearl chains, namely 3,2-chains, while 2 and 3 consist of pure 3,2-chains due to the replacement of [PMo12O40]3- with [SiW12O40]4- bearing one more negative charge. Magnetic studies revealed that all of the complexes exhibit single-chain-magnet (SCM) behaviors with the effective thermal barriers of Δτ1/kB = 61.6 K (infinite regime) and Δτ2/kB = 36.5 K (finite regime) for 1, Δτ/kB = 46.9 K for 2 (finite), and Δτ/kB = 30.6 K for 3 (finite). The POM moieties may play a pivotal role for the realization of this promising archetype of favoring SCM property: (1) the highly negatively charged POMs may facilitate the formation of the uncommon highly positive "pearl chain"; (2) the nanosized POMs necessarily led to the good isolation of the chains in the title complexes, and (3) the employment of POMs with different charges may regulate the resultant complexes in both structure and magnetism.
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Affiliation(s)
- Zi-Yi Chen
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, People's Republic of China
| | - Yue Cheng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, People's Republic of China
| | - Qi Liu
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, People's Republic of China
| | - Yi-Fei Deng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, People's Republic of China
| | - Yuan-Zhu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, People's Republic of China
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15
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Spitsyna NG, Blagov MA, Lazarenko VA, Svetogorov RD, Zubavichus YV, Zorina LV, Maximova O, Yaroslavtsev SA, Rusakov VS, Raganyan GV, Yagubskii EB, Vasiliev AN. Peculiar Spin-Crossover Behavior in the 2D Polymer K[Fe III(5Cl-thsa) 2]. Inorg Chem 2021; 60:17462-17479. [PMID: 34757728 DOI: 10.1021/acs.inorgchem.1c01821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A potassium salt of the N2S2O2-coordination Fe(III) anion K[Fe(5Cl-thsa)2] (1) (5Cl-thsa - 5-chlorosalicylaldehyde thiosemicarbazone) is synthesized and characterized structurally and magnetically over a wide temperature range. Two polymorphs of salt 1 characterized by the common 2D polymer nature and assigned to the same orthorhombic Pbcn space group have been identified. The molecular structure of the minor polymorph of 1 was solved and refined at 100, 250, and 300 K is shown to correspond to the LS configuration. The dominant polymorph of 1 features K+ cations disordered over a few crystallographic sites, while the minor polymorph includes fully ordered K+ cations. The major polymorph exhibits a complete three-step cooperative spin-crossover transition both in the heating and cooling modes: The first step occurs in a temperature range from 2 to 50 K; the second abrupt hysteretic step occurs from 200 to 250 K with T1/2 = 230 K and a 6 K hysteresis loop. The third gradual step occurs from 250 to 440 K. According to 57Fe Mössbauer, XRPD, and EXAFS data, the spin-crossover transition for the dominant polymorph is quite peculiar. Indeed, the increase in the HS concentration by 57% at the second step does not result in the expected significant increase in the iron(III)-ligand bond lengths. In addition, the final step of the spin conversion (ΔγHS = 26%) is associated with a structural phase transition with a symmetry lowering from the orthorhombic (Pbcn) to the monoclinic (P21/n) space group. This nontrivial phenomenon was investigated in detail by applying magnetization measurements, electron spin resonance, 57Fe Mössbauer spectroscopy, and DFT calculations. These results provide a new platform for understanding the multistep spin-crossover character in the Fe(III) thsa-complexes and related compounds.
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Affiliation(s)
- Nataliya G Spitsyna
- Institute of Problems of Chemical Physics, RAS, Chernogolovka, 142432, Russia
| | - Maxim A Blagov
- Institute of Problems of Chemical Physics, RAS, Chernogolovka, 142432, Russia
| | | | | | - Yan V Zubavichus
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, SB RAS, Koltsovo 630559, Russia
| | | | - Olga Maximova
- Lomonosov Moscow State University, Moscow 119991, Russia
| | | | | | | | - Eduard B Yagubskii
- Institute of Problems of Chemical Physics, RAS, Chernogolovka, 142432, Russia
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16
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Alexandru MG, Visinescu D, Cula B, Shova S, Rabelo R, Moliner N, Lloret F, Cano J, Julve M. A rare isostructural series of 3d-4f cyanido-bridged heterometallic squares obtained by assembling [Fe III{HB(pz) 3}(CN) 3] - and Ln III ions: synthesis, X-ray structure and cryomagnetic study. Dalton Trans 2021; 50:14640-14652. [PMID: 34581372 DOI: 10.1039/d1dt02512k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new series of cyanido-bridged {FeIIILnIII}2 neutral molecular squares of general formula [Fe{HB(pz)3}(CN)(μ-CN)2Ln(NO3)2(pyim)(Ph3PO)]2·2CH3CN [Ln = Ce (1), Pr (2), Nd (3), Gd (4), Tb (5), Dy (6) and Er (7); {HB(pz)3}- = hydrotris(pyrazolyl)borate, pyim = 2-(1H-imidazol-2-yl)pyridine and Ph3PO = triphenylphosphine oxide] were obtained by reacting the low-spin [Fe{HB(pz)3}(CN)3]- species with the preformed [LnIII(pyim)(NO3)2(pyim)(Ph3PO)]+ complex anions (generated in situ by mixing the nitrate salt of each Ln(III) ion with pyim and Ph3PO molecules). Single-crystal X-ray diffraction studies show that 1-7 are isostructural compounds that crystallize in the triclinic P1̄ space group. Their crystal structures consist of centrosymmetric cyanido-bridged {FeIIILnIII}2 molecular squares where two [Fe{HB(pz)3}(CN)3]- units adopt bis-monodentate coordination modes towards two [LnIII(pyim)(NO3)2(pyim)(Ph3PO)]+ moieties. The cis-oriented convergent sites from both low-spin FeIII and LnIII fragments form a quasi square-shaped molecule in which the 3d and 4f ions alternatively occupy the corners of the square. Both FeIII ions show a distorted octahedral surrounding (C3v symmetry), whereas the LnIII ions exhibit a distorted muffin-like geometry (Cs symmetry) in 1-7. The intramolecular FeIII⋯LnIII distances across the two cyanido-bridges range from ca. 5.48/5.46 up to ca. 5.58/5.61 Å. The molecular squares in 1-7 are interlinked through hydrogen bonds, weak π⋯π stacking and very weak C-H⋯π type interactions into three-dimensional supramolecular networks. The analysis of the solid-state direct-current (dc) magnetic susceptibility data of 1-7 in the temperature range 1.9-300 K reveals the occurrence of weak intra- and intermolecular antiferromagnetic interactions. The small intramolecular antiferromagnetic couplings in 4 compare well with those previously reported for parent systems. Although the coexistence of the spin-orbit coupling (SOC) of the low-spin iron(III) and lanthanide(III) ions in the remaining compounds together with the ligand field effects mask the visualization and make difficult the evaluation of the possible magnetic interactions in them, we were able to do it through a SOC model applied on exact or effective Hamiltonians. Frequency-dependent alternating current magnetic susceptibility signals in the temperature range 2.0-9.0 K under zero and non-zero static fields were observed for 5-7 which indicate slow magnetic relaxation (SMM) behavior. The usual absence of χ''M maxima moved us to estimate their energy barriers through ln(χ''M/ χ'M) vs. 1/T plots, obtaining values from 25 to 40 cm-1.
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Affiliation(s)
- Maria-Gabriela Alexandru
- Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania
| | - Diana Visinescu
- Coordination and Supramolecular Chemistry Laboratory, "Ilie Murgulescu" Institute of Physical Chemistry, Romanian Academy, Splaiul Independentei 202, Bucharest 060021, Romania.
| | - Beatrice Cula
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
| | - Sergiu Shova
- "Petru Poni" Institute of Macromolecular Chemistry, Ro, an Academy, mani, Aleea Grigore Ghica Vodă 41-A, RO-700487 Iasi, Romania
| | - Renato Rabelo
- Departament de Química Inorgànica/Instituto de Ciencia Molecular, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
| | - Nicolás Moliner
- Departament de Química Inorgànica/Instituto de Ciencia Molecular, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia Molecular, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
| | - Joan Cano
- Departament de Química Inorgànica/Instituto de Ciencia Molecular, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
| | - Miguel Julve
- Departament de Química Inorgànica/Instituto de Ciencia Molecular, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, València, Spain.
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17
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Huang W, Ma X, Sato O, Wu D. Controlling dynamic magnetic properties of coordination clusters via switchable electronic configuration. Chem Soc Rev 2021; 50:6832-6870. [PMID: 34151907 DOI: 10.1039/d1cs00101a] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Large-sized coordination clusters have emerged as a new class of molecular materials in which many metal atoms and organic ligands are integrated to synergize their properties. As dynamic magnetic materials, such a combination of multiple components functioning as responsive units has many advantages over monometallic systems due to the synergy between constituent components. Understanding the nature of dynamic magnetism at an atomic level is crucial for realizing the desired properties, designing responsive molecular nanomagnets, and ultimately unlocking the full potential of these nanomagnets for practical applications. Therefore, this review article highlights the recent development of large-sized coordination clusters with dynamic magnetic properties. These dynamic properties can be associated with spin transition, electron transfer, and valence fluctuation through their switchable electronic configurations. Subsequently, the article also highlights specialized characterization techniques with different timescales for supporting switching mechanisms, chemistry, and properties. Afterward, we present an overview of coordination clusters (such as cyanide-bridged and non-cyanide assemblies) with dynamic magnetic properties, namely, spin transition and electron transfer in magnetically bistable systems and mixed-valence complexes. In particular, the response mechanisms of coordination clusters are highlighted using representative examples with similar transition principles to gain insights into spin state and mixed-valence chemistry. In conclusion, we present possible solutions to challenges related to dynamic magnetic clusters and potential opportunities for a wide range of intelligent next-generation devices.
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Affiliation(s)
- Wei Huang
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, Advanced Catalysis & Green Manufacturing Collaborative Innovation Center, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
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18
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Visinescu D, Alexandru MG, Dumitrescu DG, Shova S, Moliner N, Lloret F, Julve M. Cyanido-bridged {Fe IIILn III} heterobimetallic chains assembled through the [Fe III{HB(pz) 3}(CN) 3] − complex as metalloligand: synthesis, crystal structure and magnetic properties. CrystEngComm 2021. [DOI: 10.1039/d1ce00626f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The first isostructural series of cyanido-bridged 3d–4f chains showing a unique zig-zag motif have been obtained by using the heteroleptic [FeIII{HB(pz)3}(CN)3]− complex as a metalloligand towards the preformed [LnIII(bpdo)(NO3)2(H2O)]+ species.
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Affiliation(s)
- Diana Visinescu
- Coordination and Supramolecular Chemistry Laboratory
- “Ilie Murgulescu” Institute of Physical Chemistry
- Romanian Academy
- Bucharest 060021
- Romania
| | - Maria-Gabriela Alexandru
- Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry
- Faculty of Applied Chemistry and Materials Science
- University Politehnica of Bucharest
- 011061 Bucharest
- Romania
| | | | - Sergiu Shova
- “Petru Poni” Institute of Macromolecular Chemistry
- Romanian Academy
- RO-700487 Iasi
- Romania
| | - Nicolás Moliner
- Departament de Química Inorgànica/Instituto de Ciencia Molecular
- Universitat de València
- 46980 Paterna
- Spain
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia Molecular
- Universitat de València
- 46980 Paterna
- Spain
| | - Miguel Julve
- Departament de Química Inorgànica/Instituto de Ciencia Molecular
- Universitat de València
- 46980 Paterna
- Spain
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19
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Zhao XH, Shao D, Chen JT, Liu M, Li T, Yang J, Zhang YZ. Spin and valence isomerism in cyanide-bridged {FeM II} (M = Fe and Co) clusters. Dalton Trans 2021; 50:9768-9774. [PMID: 34169954 DOI: 10.1039/d1dt01298c] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two cyanide-bridged V-shaped isostructural trinuclear complexes [{(Tp*)FeIII(CN)3}2MII(bztpen)]·Sol (M = Fe, Sol = CH3OH·3H2O, 1; M = Co, Sol = 2CH3OH·2H2O, 2; bztpen = N-benzyl-N,N',N'-tris(2-methylpyridyl)ethylenediamine; Tp* = hydrotris(3,5-dimethylpyrazolyl)borate) were synthesized and characterized. The bztpen ligand serves as a tetradentate capping ligand around the inner metal ion, leaving one pyridyl group intact. Complex 1 exhibits a spin crossover (SCO) behavior between the {FeIIILSFeIIHSFeIIILS} and {FeIIILSFeIILSFeIIILS} spin isomers, while 2 shows both thermally- and photo-induced electron-transfer coupled spin transition (ETCST) property between the {FeIIILSCoIIHSFeIIILS} and {FeIIILSCoIIILSFeIILS} valence isomers. The total entropy changes for 1 and 2 between their corresponding two electronic states were found to be very close with the values of 87.46 and 84.49 J mol-1 K-1, respectively, indicating the comparable thermal energy barriers necessary for either an SCO or ETCST event for such a given system. Furthermore, both complexes undergo desolvation-induced irreversible and sharp magnetic change at high temperatures.
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Affiliation(s)
- Xin-Hua Zhao
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
| | - Dong Shao
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
| | - Jia-Tao Chen
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
| | - Min Liu
- College of Nuclear Science and Technology, University of South China, Hengyang, 421001, P. R. China
| | - Tao Li
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
| | - Jiong Yang
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
| | - Yuan-Zhu Zhang
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.
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20
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Yang J, Zhao XH, Deng YF, Zhang XY, Chang XY, Zheng Z, Zhang YZ. Azido-Cyanide Mixed-Bridged Fe III-Ni II Complexes. Inorg Chem 2020; 59:16215-16224. [PMID: 33105988 DOI: 10.1021/acs.inorgchem.0c01917] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The successful introduction of azide ions as secondary bridges into the FeIII-NiII cyanide system afforded two clusters and one unique 4(3),2-ribbon chain: [(bpzpy)2Ni2(μ2-1,1-N3)2{(pzTp)Fe(CN)3}2]·3H2O [1; bpzpy = 2,6-bis(pyrazol-1-yl)pyridine, and pzTp = tetrakis(pyrazolyl)borate], [(L1)2Ni4(μ3-1,1,1-OCH3)2(μ2-1,1-N3)2(H2O)2{(Tp)Fe(CN)3}2]·2CH3OH·H2O [2; Tp = hydrotris(pyrazolyl)borate, and HL1 = 2,6-bis{(2-hydroxypropylimino)methyl}-4-methylphenol], and [(L2)2Ni3(μ2-1,1-N3)4{(pzTp)Fe(CN)3}2]n (3; L2 = 2-{[phenyl(pyridin-2-yl)methylene]amino}ethan-1-amine). Both 1 and 2 feature the centrosymmetric {FeIII-NiII2-FeIII} and {FeIII-NiII4-FeIII} rodlike structures in which the two peripheral [(TpR)Fe(CN)3]- anions act as monodentate ligands via one cyanide group to link the central azide-bridged [Ni2] and [Ni4] subunit, respectively, while 3 displays an extended structure of the double-zigzag (4,2-ribbon) chain in which the double end-on azide-bridged trinuclear [Ni3] subunits serve as the 4-connected nodes. Magnetic study revealed that intramolecular ferromagnetic coupling is dominated by the azide or cyanide bridges in all of the complexes. Remarkably, complex 1 behaves as a single-molecule magnet with an effective energy barrier of 16.5 cm-1 at zero dc field, while complex 3 exhibits metamagnetism with a hidden spin canting property below 12 K.
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Affiliation(s)
- Jiong Yang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Xin-Hua Zhao
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yi-Fei Deng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Xin-Yu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Xiao-Yong Chang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Zhiping Zheng
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Yuan-Zhu Zhang
- Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
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21
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Chen D, Wang SY, Wang K, Li QW, Yang C, Wang QL. Four bimetallic chiral magnetic materials derived from octacyanometalate and cyclohexanediamine. INORG CHEM COMMUN 2020. [DOI: 10.1016/j.inoche.2020.108171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Kitase K, Kitazawa T. A novel two-step Fe-Au type spin-crossover behavior in a Hofmann-type coordination complex {Fe(4-methylpyrimidine) 2[Au(CN) 2] 2}. Dalton Trans 2020; 49:12210-12214. [PMID: 32608445 DOI: 10.1039/d0dt01681k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A Hofmann-type two-step spin-crossover (SCO) complex with a pyrimidine derivative ligand, Fe(4-methylpyrimidine)2[Au(CN)2]2, was synthesized, and this complex shows a two-step SCO phenomenon in the intermediate state. Symmetry breaking also occurs in the intermediate state. These results reveal three spin states within the complex for high-spin (HS), HS0.5LS0.5, and low-spin (LS).
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Affiliation(s)
- Kosuke Kitase
- Department of Chemistry, Toho University, Chiba 274-8510, Japan.
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23
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Chen JT, Zhao XH, Zhang YZ. Manipulating the spin crossover behavior in a series of {FeIII2FeII} complexes. Dalton Trans 2020; 49:5949-5956. [DOI: 10.1039/d0dt00016g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three cyanide-bridged {Fe2Fe} complexes are reported to exhibit excellent SCO properties which are highly dependent on the compact degree of the π-π stacking, the loss of lattice solvents as well as the electron-donor strength of TpR.
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Affiliation(s)
- Jia-Tao Chen
- Department of Chemistry
- Southern University of Science and Technology
- Shenzhen
- P. R. China
| | - Xin-Hua Zhao
- Department of Chemistry
- Southern University of Science and Technology
- Shenzhen
- P. R. China
| | - Yuan-Zhu Zhang
- Department of Chemistry
- Southern University of Science and Technology
- Shenzhen
- P. R. China
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