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Kühne IA, Ozarowski A, Sultan A, Esien K, Carter AB, Wix P, Casey A, Heerah-Booluck M, Keene TD, Müller-Bunz H, Felton S, Hill S, Morgan GG. Homochiral Mn 3+ Spin-Crossover Complexes: A Structural and Spectroscopic Study. Inorg Chem 2022; 61:3458-3471. [PMID: 35175771 PMCID: PMC8889584 DOI: 10.1021/acs.inorgchem.1c03379] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Structural, magnetic,
and spectroscopic data on a Mn3+ spin-crossover complex
with Schiff base ligand 4-OMe-Sal2323, isolated in crystal
lattices with five different counteranions,
are reported. Complexes of [Mn(4-OMe-Sal2323)]X where X
= ClO4– (1), BF4– (2), NO3– (3), Br– (4), and I– (5) crystallize isotypically in the chiral
orthorhombic space group P21212 with a range of spin state preferences for the [Mn(4-OMe-Sal2323)]+ complex cation over the temperature range
5–300 K. Complexes 1 and 2 are high-spin,
complex 4 undergoes a gradual and complete thermal spin
crossover, while complexes 3 and 5 show
stepped crossovers with different ratios of spin triplet and quintet
forms in the intermediate temperature range. High-field electron paramagnetic
resonance was used to measure the zero-field splitting parameters
associated with the spin triplet and quintet states at temperatures
below 10 K for complexes 4 and 2 with respective
values: DS=1 = +23.38(1) cm–1, ES=1 = +2.79(1) cm–1,
and DS=2 =
+6.9(3) cm–1, with a distribution of E parameters for the S = 2 state. Solid-state circular
dichroism (CD) spectra on high-spin complex 1 at room
temperature reveal a 2:1 ratio of enantiomers in the chiral conglomerate,
and solution CD measurements on the same sample in methanol show that
it is stable toward racemization. Solid-state UV–vis absorption
spectra on high-spin complex 1 and mixed S = 1/S = 2 sample 5 reveal different
intensities at higher energies, in line with the different electronic
composition. The statistical prevalence of homochiral crystallization
of [Mn(4-OMe-Sal2323)]+ in five lattices with
different achiral counterions suggests that the chirality may be directed
by the 4-OMe-Sal2323 ligand. Zero-field
splitting parameters of the spin triplet and
quintet forms of a spin-crossover Mn3+ complex stabilized
in lattices with different counterions are measured by high-field
electron paramagnetic resonance at different frequencies. The homochiral
crystallization of the enantiopure Δ or Λ forms of the
chelate complex, despite the use of achiral anions, is attributed
to the steric influence of the ligand substituent.
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Affiliation(s)
- Irina A Kühne
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.,FZU - Institute of Physics - Czech Academy of Sciences, Na Slovance 1999/2, Prague 8 182 21, Czech Republic
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Aizuddin Sultan
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Kane Esien
- School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom
| | - Anthony B Carter
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Paul Wix
- School of Chemistry & CRANN Institute & AMBER Centre, Trinity College Dublin, University of Dublin, College Green, Dublin 2, Ireland
| | - Aoife Casey
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | | | - Tony D Keene
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Helge Müller-Bunz
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Solveig Felton
- School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom
| | - Stephen Hill
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States.,Department of Physics, Florida State University, Tallahassee, Florida 32306, United States
| | - Grace G Morgan
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland
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2
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Sundaresan S, Kühne IA, Evesson C, Harris MM, Fitzpatrick AJ, Ahmed A, Müller-Bunz H, Morgan GG. Compressed Jahn-Teller octahedra and spin quintet-triplet switching in coordinatively elastic manganese(III) complexes. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115386] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Synthesis, Crystal Structure and Magnetic Properties of 1D Chain Complexes Based on Azo Carboxylate Oxime Ligand. MAGNETOCHEMISTRY 2021. [DOI: 10.3390/magnetochemistry7070105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Two carboxylate-bridged one-dimensional chain complexes, {[MnII(MeOH)2][FeIII(L)2]2}n (1) and {[MnII(DMF)2][MnIII(L)2]2·DMF}n (2) [H2L = ((2-carboxyphenyl)azo)-benzaldoxime], containing a low-spin [FeIII(L)2]− or [MnIII(L)2]− unit were synthesized. Magnetic measurements show that the adjacent high-spin MnII and low-spin MIII ions display weak antiferromagnetic coupling via the syn–anti carboxyl bridges, with J = −0.066(2) cm−1 for complex 1 and J = −0.274(2) cm−1 for complex 2.
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4
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Dinda S, Roy S, Patra SC, Bhandary S, Pramanik K, Ganguly S. Polyaromatic hydrocarbon derivatized azo-oximes of cobalt( iii) for the ligand-redox controlled electrocatalytic oxygen reduction reaction. NEW J CHEM 2020. [DOI: 10.1039/c9nj05527d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two new polyaromatic hydrocarbon (PAH) derivatized cobalt(iii) azo-oxime complexes were synthesized and their activity in electrocatalytic oxygen reduction reaction (ORR) were explored.
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Affiliation(s)
- Soumitra Dinda
- Department of Chemistry
- St. Xavier's College (Autonomous)
- Kolkata–700016
- India
| | - Syamantak Roy
- Molecular Materials Laboratory
- Chemistry and Physics of Materials Unit
- Jawaharlal Nehru Centre for Advanced Scientific Research
- Jakkur
- Bangalore
| | | | - Subhrajyoti Bhandary
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal By-pass Road
- Bhauri
- Bhopal
| | | | - Sanjib Ganguly
- Department of Chemistry
- St. Xavier's College (Autonomous)
- Kolkata–700016
- India
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5
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Barker A, Kelly CT, Kühne IA, Hill S, Krzystek J, Wix P, Esien K, Felton S, Müller-Bunz H, Morgan GG. Spin state solvomorphism in a series of rare S = 1 manganese(iii) complexes. Dalton Trans 2019; 48:15560-15566. [PMID: 31342029 DOI: 10.1039/c9dt02476j] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Structural, magnetic and spectroscopic data of four complex salts, [Mn(napsal2323)]NTf2, 1,[Mn(napsal2323)]ClO4, 2, [Mn(napsal2323)]BF4, 3 and [Mn(napsal2323)]NO3, 4, of the [Mn(napsal2323)]+ complex cation indicate that the Mn3+ ion is stabilized in the rare S = 1 spin triplet form in this ligand sphere. Zero-field splitting values of D = +19.6 cm-1 and |E| = 2.02 cm-1 for complex 1 were obtained by High Field Electron Paramagnetic Resonance (HFEPR) measurements conducted over a range of frequencies. Structural and magnetic data also indicate that co-crystallization of complexes 2 and 3 with 0.5 equivalents of ethanol yields the high spin S = 2 forms of the perchlorate and tetrafluoroborate solvates [Mn(napsal2323)]ClO4·0.5(C2H5OH), 2·0.5EtOH and [Mn(napsal2323)]BF4·0.5(C2H5OH), 3·0.5EtOH.
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Affiliation(s)
- Andrew Barker
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
| | - Conor T Kelly
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
| | - Irina A Kühne
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
| | - Stephen Hill
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA and Department of Physics, Florida State University, Tallahassee, FL 32306, USA
| | - J Krzystek
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - Paul Wix
- School of Chemistry & CRANN Institute, Trinity College Dublin, University of Dublin, College Green, Dublin 2, Ireland
| | - Kane Esien
- Centre for Nanostructured Media (CNM), School of Mathematics and Physics, Queen's University Belfast, Belfast, BT7 1NN, UK
| | - Solveig Felton
- Centre for Nanostructured Media (CNM), School of Mathematics and Physics, Queen's University Belfast, Belfast, BT7 1NN, UK
| | - Helge Müller-Bunz
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
| | - Grace G Morgan
- School of Chemistry, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
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6
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Castañeda R, Harriman KLM, Wong JWL, Gabidullin B, Murugesu M, Brusso JL. Rational Design of Tetranuclear Complexes Employing
N
‐Imidoylamidine Based Ligands. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Raúl Castañeda
- Department of Chemistry and Biomolecular Sciences University of Ottawa 10 Marie Curie Ottawa Ontario K1N 6N5 Canada
| | - Katie L. M. Harriman
- Department of Chemistry and Biomolecular Sciences University of Ottawa 10 Marie Curie Ottawa Ontario K1N 6N5 Canada
| | - Joanne W. L. Wong
- Institut für Anorganische Chemie Georg‐August‐Universität Göttingen Tammannstraße 4 37077 Göttingen Germany
| | - Bulat Gabidullin
- Department of Chemistry and Biomolecular Sciences University of Ottawa 10 Marie Curie Ottawa Ontario K1N 6N5 Canada
| | - Muralee Murugesu
- Department of Chemistry and Biomolecular Sciences University of Ottawa 10 Marie Curie Ottawa Ontario K1N 6N5 Canada
| | - Jaclyn L. Brusso
- Department of Chemistry and Biomolecular Sciences University of Ottawa 10 Marie Curie Ottawa Ontario K1N 6N5 Canada
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7
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Colmer HE, Margarit CG, Smith JM, Jackson TA, Telser J. Spectroscopic and Computational Investigation of Low-Spin Mn(III) Bis(scorpionate) Complexes. Eur J Inorg Chem 2016; 2016:2413-2423. [PMID: 28713219 PMCID: PMC5507630 DOI: 10.1002/ejic.201501250] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Indexed: 11/06/2022]
Abstract
Six-coordinate MnIII complexes are typically high-spin (S = 2), however, the scorpionate ligand, both in its traditional, hydridotris(pyrazolyl)borate form, Tp- and Tp*- (the latter with 3,5-dimethylpyrazole substituents) and in an aryltris(carbene)borate (i.e., N-heterocyclic carbene, NHC) form, [Ph(MeIm)3B]-, (MeIm = 3-methylimidazole) lead to formation of bis(scorpionate) complexes of MnIII with spin triplet ground states; three of which were investigated herein: [Tp2Mn]SbF6 (1SBF6), [Tp*2Mn]SbF6 (2SBF6), and [{Ph(MeIm)3B}2Mn]CF3SO3 (3CF3SO3). These trigonally symmetric complexes were studied experimentally by magnetic circular dichroism (MCD) spectroscopy (the propensity of 3 to oxidize to MnIV precluded collection of useful MCD data) including variable temperatures and fields (VTVH-MCD) and computationally by ab initio CASSCF/NEVPT2 methods. These combined experimental and theoretical techniques establish the 3A2g electronic ground state for the three complexes, and provide information on the energy of the "conventional" high-spin excited state (5Eg) and other, triplet excited states. These results show the electronic effect of pyrazole ring substituents in comparing 1 and 2. The tunability of the scorpionate ligand, even by perhaps the simplest change (from pyrazole in 1 to 3,5-dimethylpyrazole in 2) is quantitatively manifested through perturbations in ligand-field excited-state energies that impact ground-state zero-field splittings. The comparison with the NHC donor is much more dramatic. In 3, the stronger σ-donor properties of the NHC lead to a quantitatively different electronic structure, so that the lowest lying spin triplet excited state, 3Eg, is much closer in energy to the ground state than in 1 or 2. The zero-field splitting (zfs) parameters of the three complexes were calculated and in the case of 1 and 2 compare closely to experiment (lower by < 10%, < 2 cm-1 in absolute terms); for 3 the large magnitude zfs is reproduced, although there is ambiguity about its sign. The comprehensive picture obtained for these bis(scorpionate) MnIII complexes provides quantitative insight into the role played by the scorpionate ligand in stabilizing unusual electronic structures.
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Affiliation(s)
- Hannah E Colmer
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045 USA
| | - Charles G Margarit
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003 USA
| | - Jeremy M Smith
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003 USA
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405 USA
| | - Timothy A Jackson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045 USA
| | - Joshua Telser
- Department of Biological, Chemical and Physical Sciences, Roosevelt University, Chicago, Illinois 60605 USA
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8
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Pramanik S, Roy S, Ghorui T, Ganguly S, Pramanik K. Iridium(III) Mediated Reductive Transformation of Closed-Shell Azo-Oxime to Open-Shell Azo-Imine Radical Anion: Molecular and Electronic Structure, Electron Transfer, and Optoelectronic Properties. Inorg Chem 2016; 55:1461-8. [DOI: 10.1021/acs.inorgchem.5b02185] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shuvam Pramanik
- Department
of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Sima Roy
- Department
of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Tapas Ghorui
- Department
of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Sanjib Ganguly
- Department
of Chemistry, St. Xavier’s College, Kolkata 700016, India
| | - Kausikisankar Pramanik
- Department
of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
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9
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Synthesis, structures, and magnetic properties of carboxylate-bridged trinuclear complexes based on low-spin manganese(III)/iron(III) building blocks. TRANSIT METAL CHEM 2013. [DOI: 10.1007/s11243-013-9737-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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11
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Romain S, Duboc C, Neese F, Rivière E, Hanton L, Blackman A, Philouze C, Leprêtre JC, Deronzier A, Collomb MN. An Unusual Stable Mononuclear MnIIIBis-terpyridine Complex Exhibiting Jahn-Teller Compression: Electrochemical Synthesis, Physical Characterisation and Theoretical Study. Chemistry 2008; 15:980-8. [DOI: 10.1002/chem.200801442] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Mantel C, Chen H, Crabtree RH, Brudvig GW, Pécaut J, Collomb MN, Duboc C. High-Spin Chloro Mononuclear MnIIIComplexes: A Multifrequency High-Field EPR Study. Chemphyschem 2005; 6:541-6. [PMID: 15799481 DOI: 10.1002/cphc.200400484] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The isolation, structural characterization, and electronic properties of two six-coordinated chloromanganese (III) complexes, [Mn(terpy)(Cl)3] (1) and [Mn(Phterpy)(Cl)3] (2), are reported (terpy = 2,2':6'2"-terpyridine, Phterpy = 4'-phenyl-2,2':6',2"-terpyridine). These complexes complement a series of mononuclear azide and fluoride Mn(lll) complexes synthesized with neutral N-tridentate ligands, [Mn(L)(X)3] (X = F- or N3 and L = terpy or bpea [N,N-bis(2-pyridylmethyl)-ethylamine)], previously described. Similar to these previous complexes, 1 and 2 exhibit a Jahn-Teller distortion of the octahedron, characteristic of a high-spin Mn(III) complex (S = 2). The analysis of the crystallographic data shows that, in both cases, the manganese ion lies in the center of a distorted octahedron characterized by an elongation along the tetragonal axis. Their electronic properties were investigated by multifrequency EPR (190-475 GHz) performed in the solid state at different temperatures (5-15 K). This study confirms our previous results and further shows that: i) the sign of D is correlated with the nature of the tetragonal distortion; ii) the magnitude of D is not sensitive to the nature of the anions in our series of rhombic complexes, contrary to the porphyrinic systems; iii) the [E/D] values (0.124 for 1 and 0.085 for 2) are smaller compared to those found for the [Mn(L)(X)3] complexes (in the range of 0.146 to 0.234); and iv) the E term increases when the ligand-field strength of the equatorial ligands decreases.
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Affiliation(s)
- Claire Mantel
- High Magnetic Field Laboratory of Grenoble, HMFL, CNRS-MPI UPR 5021 BP 166, F 38042 Grenoble 9, France
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13
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Mantel C, Hassan AK, Pécaut J, Deronzier A, Collomb MN, Duboc-Toia C. A high-frequency and high-field EPR study of new azide and fluoride mononuclear Mn(III) complexes. J Am Chem Soc 2004; 125:12337-44. [PMID: 14519019 DOI: 10.1021/ja034652+] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The isolation, structural characterization and electronic properties of three new six-coordinated Mn(III) complexes, [Mn(bpea)(F)(3)] (1), [Mn(bpea)(N(3))(3)] (2), and [Mn(terpy)(F)(3)] (3) are reported (bpea = N,N-bis(2-pyridylmethyl)-ethylamine; terpy = 2,2':6',2' '-terpyridine). As for [Mn(terpy)(N(3))(3)] (4) (previously described by Limburg J.; Vrettos J. S.; Crabtree R. H.; Brudvig G. W.; de Paula J. C.; Hassan A.; Barra A-L.; Duboc-Toia C.; Collomb M-N. Inorg. Chem. 2001, 40, 1698), all these complexes exhibit a Jahn-Teller distortion of the octahedron characteristic of high-spin Mn(III) (S = 2). The analysis of the crystallographic data shows an elongation along the tetragonal axis of the octahedron for complexes 1 and 3, while complex 2 presents an unexpected compression. The electronic properties were investigated using a high-field and high-frequency EPR study performed between 5 and 15 K (190-575 GHz). The spin Hamiltonian parameters determined in solid state are in agreement with the geometry of the complexes observed in the crystal structures. A negative D value found for 1 and 3 is related to the elongated tetragonal distortion, whereas the positive D value determined for 2 is in accordance with a compressed octahedron. The high E/D values, in the range of 0.103 to 0.230 for all complexes, are correlated with the highly distorted geometry present around the Mn(III) ion. HF-EPR experiments were also performed on complex 1 in solution and show that the D value is the only spin Hamiltonian parameter which is slightly modified compared to the solid state (D = -3.67 cm(-1) in solid state; D = -3.95 cm(-1) in solution).
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Affiliation(s)
- Claire Mantel
- Grenoble High Magnetic Field Laboratory, MPI-CNRS UPR 5021, BP 166, 38042 Grenoble Cedex 9, France
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14
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De Alwis DCL, Schultz FA. Metal-bis[poly(pyrazolyl)borate] complexes. Electrochemical, magnetic, and spectroscopic properties and coupled electron-transfer and spin-exchange reactions. Inorg Chem 2003; 42:3616-22. [PMID: 12767201 DOI: 10.1021/ic034077a] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electrochemical, magnetic, and spectroscopic properties are reported for homoleptic divalent (M = Mn, Fe, Co, Ni, Ru) and trivalent (M = Cr, Mn, Fe, Co) metal-bis[poly(pyrazolyl)borate] complexes, [M(pzb)(2)](+/0), where pzb(-) = hydrotris(pyrazolyl)borate (Tp), hydrotris(3,5-dimethylpyrazolyl)borate (Tp), or tetrakis(pyrazolyl)borate (pzTp). Ligand field strengths in metal-pzb complexes increase as Tp < Tp < pzTp, which reflects the importance of steric rather than electronic effects on spectroscopic properties. However, metal-centered redox potentials become more negative as pzTp < Tp < Tp, which follows the electron-donating ability of the ligands. Co(III)/Co(II) and Mn(III)/Mn(II) electrode reactions are accompanied by a change in metal atom spin-state; i.e., (S = 0) [Co(pzb)(2)](+) + e(-) <==> (S = 3/2) [Co(pzb)(2)] and (S = 1) [Mn(pzb)(2)](+) + e(-) <==> (S = 5/2) [Mn(pzb)(2)]. Apparent heterogeneous electron-transfer rate constants derived from sweep-rate dependent cyclic voltammetric peak potential separations in 1,2-dichloroethane are small and decrease as pzTp > Tp > Tp for the Co(III)/Co(II) couples. Slow electron transfer is characteristic of coupled electron transfer and spin exchange. [M(Tp)(2)](+/0) redox potentials relative to values for other homoleptic MN(6)(3+/2+) couples change as M varies from Cr to Ni. For early members of the series, [M(Tp)(2)](+/0) potentials nearly equal those of complexes with aliphatic N-donor ligands (e.g., triazacyclononane, sarcophagine). However, [M(Tp)(2)](+/0) potentials approach those of [M(bpy)(3)](3+/2+) for later members of the series. The variation suggests a change in the nature of the metal-pzb interaction upon crossing the first transition row.
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Affiliation(s)
- D Chanaka L De Alwis
- Department of Chemistry, Indiana University Purdue University Indianapolis, 402 North Blackford Street, Indianapolis, Indiana 46202-3274, USA
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15
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Matsumoto N, Sunatsuki Y, Miyasaka H, Hashimoto Y, Luneau D, Tuchagues JP. [{Mn(salen)CN}n]: die erste metamagnetische, eindimensionale Kette mit alternierenden High-spin- und Low-spin-MnIII-Zentren. Angew Chem Int Ed Engl 1999. [DOI: 10.1002/(sici)1521-3757(19990115)111:1/2<137::aid-ange137>3.0.co;2-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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