Yanhua Lan - Academia.edu (original) (raw)
Papers by Yanhua Lan
Chemistry - A European Journal, 2017
Advanced materials (Deerfield Beach, Fla.), 2016
In Tb(Pc)2 single-molecule magnets, where Pc is phthalocyanine, adsorbed on magnesium oxide, the ... more In Tb(Pc)2 single-molecule magnets, where Pc is phthalocyanine, adsorbed on magnesium oxide, the fluctuations of the terbium magnetic moment are strongly suppressed in contrast to the adsorption on silver. On page 5195, J. Dreiser and co-workers investigate that the molecules are perfectly organized by self-assembly, as seen in the scanning tunnelling microscopy image (top part of the design). The molecules are probed by circularly polarized X-rays depicted as green spirals.
Chemistry - A European Journal, 2016
This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 4, 2016
The chemically and structurally highly stable polyoxometalate (POM) single-molecule magnet (SMM) ... more The chemically and structurally highly stable polyoxometalate (POM) single-molecule magnet (SMM) [(FeW9 O34 )2 Fe4 (H2 O)2 ](10-) (Fe6 W18 ) has been incorporated by direct or post-synthetic approaches into a biopolymer gelatin (Gel) matrix and two crystalline metal-organic frameworks (MOFs), including one diamagnetic (UiO-67) and one magnetic (MIL-101(Cr)). Integrity of the POM in the Fe6 W18 @Gel, Fe6 W18 @UiO-67 and Fe6 W18 @MIL-101(Cr) composites was confirmed by a set of complementary techniques. Magnetic studies indicate that the POMs are magnetically well isolated. Remarkably, in Fe6 W18 @Gel, the SMM properties of the embedded molecules are close to those of the crystals, with clear quantum tunneling steps in the hysteresis loops. For the Fe6 W18 @UiO-67 composite, the molecules retain their SMM properties, the energy barrier being slightly reduced in comparison to the crystalline material and the molecules exhibiting a tunneling rate of magnetization significantly faster th...
Journal of the American Chemical Society, Apr 27, 2016
Single-molecule magnets (SMMs) with a large spin reversal barrier have been recognized to exhibit... more Single-molecule magnets (SMMs) with a large spin reversal barrier have been recognized to exhibit slow magnetic relaxation that can lead to a magnetic hysteresis loop. Synthesis of highly stable SMMs with both large energy barriers and significantly slow relaxation times is challenging. Here, we report two highly stable and neutral Dy(III) classical coordination compounds with pentagonal bipyramidal local geometry that exhibit SMM behavior. Weak intermolecular interactions in the undiluted single crystals are first observed for mononuclear lanthanide SMMs by micro-SQUID measurements. The investigation of magnetic relaxation reveals the thermally activated quantum tunneling of magnetization through the third excited Kramers doublet, owing to the increased axial magnetic anisotropy and weaker transverse magnetic anisotropy. As a result, pronounced magnetic hysteresis loops up to 14 K are observed, and the effective energy barrier (Ueff = 1025 K) for relaxation of magnetization reached...
Inorganic Chemistry, 2009
European Journal of Inorganic Chemistry, 2014
ABSTRACT 2-Amino-4-(2-pyridyl)thiazole (H2L) complexes of iron(III), iron(II), cobalt(II), nickel... more ABSTRACT 2-Amino-4-(2-pyridyl)thiazole (H2L) complexes of iron(III), iron(II), cobalt(II), nickel(II) and copper(II) have been prepared for the first time. The oxido-bridged dinuclear ferric complex [(H2L)2FFeIII(μ-O)FeIIIF(H2L)2](BF4)2 (1) and the mononuclear difluorido complex [FeIII(H2L)2F2](BF4) (2) were prepared with Fe(BF4)2·6H2O. Complex 1 contains strong antiferromagnetically coupled iron(III) ions. In addition, the mononuclear 3:1-type complex [Co(H2L)3](ClO4)2 (3) and the mononuclear 2:1-type complexes [Cu(H2L)2](ClO4)2 (4) and [M(H2L)2(NCX)2] (5: M = Fe, X = S; 6: M = Fe, X = Se; 7: M = Co, X = S; 8: M = Ni, X = S) were prepared.
Layfield/Lanthanides and Actinides in Molecular Magnetism, 2015
Chemistry - A European Journal, 2015
Ad isk-shaped [Fe III 7 (Cl)(MeOH) 6 (m 3-O) 3 (m-OMe) 6 (PhCO 2) 6 ]Cl 2 complex with C 3 symmet... more Ad isk-shaped [Fe III 7 (Cl)(MeOH) 6 (m 3-O) 3 (m-OMe) 6 (PhCO 2) 6 ]Cl 2 complex with C 3 symmetryh as been synthesised and characterised.T he central tetrahedralF e III is 0.733 a bove the almost co-planar Fe III 6 wheel,t ow hichi t is connected through three m 3-oxide bridges.F or this ironoxo core, the magnetic susceptibility analysisproposed aHeisenberg-Dirac-van Vleck (HDvV) mechanism that leads to an intermediate spin ground state of S = 7/2 or 9/2. Within either of these grounds tate manifolds it is reasonable to expect spin frustratione ffects. The 57 Fe Mçssbauer (MS) analysis verifies that the central Fe III ione asily aligns its magnetic momenta ntiparallel to the externallya ppliedfield direction, whereast he other six peripheral Fe III ions keep their momentsa lmost perpendicular to the field at strongerf ields. This unusual canted spin structure reflects spin frustration. The small linewidths in the magnetic Mçssbauer spectra of polycrystallinesamplesc learlysuggesta nisotropic exchange mechanism for realisation of this peculiar spin topology.
Inorganic Chemistry, 2015
Reactions of the N-substituted diethanolamine ligand N-n-butyldiethanolamine with chromium(II) an... more Reactions of the N-substituted diethanolamine ligand N-n-butyldiethanolamine with chromium(II) and lanthanide(III)/rare earth salts (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) in the presence of coligands give access to three series of isostructural 1:1 3d(Cr(III))/4f(Ln(III)) coordination cluster compounds that can be designated in terms of octanuclear "square-in-square" (Ln = La-Tb), hexanuclear "triangle-in-triangle" (Ln = Dy, Ho, Y) and tetranuclear "butterfly" or defect dicubane core (Ln = Er-Lu) topologies as revealed by single-crystal X-ray crystallographic analysis. The bulk magnetic properties were also measured. The influences of the various components in the reaction system on the final topology and the role of the ionic radius are discussed.
Rsc Advances, 2013
ABSTRACT The synthesis, structural characterization, magnetic and catalytic properties of a new c... more ABSTRACT The synthesis, structural characterization, magnetic and catalytic properties of a new class of lanthanide-containing cationic heteropolyoxovanadium clusters with a nanochocolate-like structure are reported. The title 10 compounds were characterized by single-crystal and powder X-ray diffraction, IR and 51 V-NMR spectroscopies and magnetic susceptibility measurements.
European Journal of Inorganic Chemistry, 2014
ABSTRACT A series of 2,6-bis(hydroxymethyl)-4-R-phenol ligands (H3LR; R = H, F, Cl, Br, I, Ph, NH... more ABSTRACT A series of 2,6-bis(hydroxymethyl)-4-R-phenol ligands (H3LR; R = H, F, Cl, Br, I, Ph, NH2, NO2, SMe) have either been newly synthesized or the existing syntheses have been significantly improved to investigate ligand-functionalized analogues of the previously published coordination cluster [MnIII12MnII7(μ4-O)8(μ3-N3)8(HLMe)12(MeCN)6]Cl2·10MeOH·MeCN (1) with S = 83/2. The crystal structures and magnetic properties of three such Mn19 clusters, namely, [MnIII12MnII7(μ4-O)8(HLH)12(μ3-Cl)7(μ3-OMe)(MeOH)6]Cl2·16H2O·10MeOH·MeCN (3), [MnIII12MnII7(μ4-O)8(HLI)12(μ3-N3)8(MeOH)6](O2CH)2·16MeOH·10MeCN (4) and [MnIII12MnII7(μ4-O)8(μ3-Cl)7.7(μ3-OMe)0.3(HLSMe)12(MeOH)6]Cl2·27MeOH (5) are reported and compared to those of the parent cluster. When these ligands are functionalized with substituents of moderate electronegativity, it is possible to synthesize Mn19 analogues; however, when such ligands bear highly electron-donating (amino) or -withdrawing (nitro) substituents, the Mn19 analogues are no longer accessible. The Mn19 cluster framework is both magnetically and structurally robust with respect to the electron-donor/acceptor characteristics of the ligand substituent; therefore, the Mn19 system is an excellent platform for peripheral chemical engineering.
Inorganic Chemistry, 2014
Eleven new mononuclear manganese(III) complexes prepared from two hexadentate ligands, L1 and L2,... more Eleven new mononuclear manganese(III) complexes prepared from two hexadentate ligands, L1 and L2, with different degrees of steric bulk in the substituents are reported. L1 and L2 are Schiff bases resulting from condensation of N,N'-bis(3-aminopropyl)ethylenediamine with 3-methoxy-2-hydroxybenzaldehyde and 3-ethoxy-2-hydroxybenzaldehyde respectively, and are members of a ligand series we have abbreviated as R-Sal2323 to indicate the 323 alkyl connectivity in the starting tetraamine and the substitution (R) on the phenolate ring. L1 hosts a methoxy substituent on both phenolate rings, while L2 bears a larger ethoxy group in the same position. Structural and magnetic properties are reported in comparison with those of a previously reported analogue with L1, namely, [MnL1]NO3, (1e). The BPh4(-) and PF6(-) complexes [MnL1]BPh4, (1a), [MnL2]BPh4, (2a), [MnL1]PF6, (1b'), and [MnL2]PF6, (2b), with both ligands L1 and L2, remain high-spin (HS) over the measured temperature range. However, the monohydrate of (1b') [MnL1]PF6·H2O, (1b), shows gradual spin-crossover (SCO), as do the ClO4(-), BF4(-), and NO3(-) complexes [MnL1]ClO4·H2O, (1c), [MnL2]ClO4, (2c), [MnL1]BF4·H2O, (1d), [MnL2]BF4·0.4H2O, (2d), [MnL1]NO3, (1e), and [MnL2]NO3·EtOH, (2e). The three complexes formed with ethoxy-substituted ligand L2 all show a higher T1/2 than the analogous complexes with methoxy-substituted ligand L1. Analysis of distortion parameters shows that complexes formed with the bulkier ligand L2 exhibit more deformation from perfect octahedral geometry, leading to a higher T1/2 in the SCO examples, where T1/2 is the temperature where the spin state is 50% high spin and 50% low spin. Spin state assignment in the solid state is shown to be solvate-dependent for complexes (1b) and (2e), and room temperature UV-visible and NMR spectra indicate a solution-state spin assignment intermediate between fully HS and fully low spin in 10 complexes, (1a)-(1e) and (2a)-(2e).
Supramolecular Chemistry, 2012
A systematic investigation into the coordination chemistry of Mn salicylates is presented reveali... more A systematic investigation into the coordination chemistry of Mn salicylates is presented revealing the influence on the shape and dimensionality of the final products of base, the presence or absence of co-ligands and the substituents on the salicylates. We report the synthesis, structures, characterisation and magnetic properties of seven compounds, (NHEt3)[Mn(3-MeOsal)2(MeOH)(H2O)] (1), [NaMn(3-MeO-sal)2(MeOH)2] (2), [NaMn(sal)2(H2O)(MeOH)] · (MeOH) (3), [KMn(sal)2(H2O)(MeOH)] · (MeOH) (4), [MnMn 2(3-MeOsal)4(py)6(H2O)2] · 4H2O,
Inorganica Chimica Acta, 2010
The dinickel (II) compound [Ni2 (μ-OAc) 2 (OAc) 2 (μ-H2O)(asy· dmen) 2]· 2.5 H2O, 1; undergoes fa... more The dinickel (II) compound [Ni2 (μ-OAc) 2 (OAc) 2 (μ-H2O)(asy· dmen) 2]· 2.5 H2O, 1; undergoes facile reaction in a 1: 2 molar ratio with benzohydroxamic acid (BHA) in ethanol to give the novel nickel (II) tetranuclear hydroxamate complex [Ni4 (μ-OAc) 3 (μ-BA) 3 (asy ...
Chemistry - A European Journal, 2017
Advanced materials (Deerfield Beach, Fla.), 2016
In Tb(Pc)2 single-molecule magnets, where Pc is phthalocyanine, adsorbed on magnesium oxide, the ... more In Tb(Pc)2 single-molecule magnets, where Pc is phthalocyanine, adsorbed on magnesium oxide, the fluctuations of the terbium magnetic moment are strongly suppressed in contrast to the adsorption on silver. On page 5195, J. Dreiser and co-workers investigate that the molecules are perfectly organized by self-assembly, as seen in the scanning tunnelling microscopy image (top part of the design). The molecules are probed by circularly polarized X-rays depicted as green spirals.
Chemistry - A European Journal, 2016
This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 4, 2016
The chemically and structurally highly stable polyoxometalate (POM) single-molecule magnet (SMM) ... more The chemically and structurally highly stable polyoxometalate (POM) single-molecule magnet (SMM) [(FeW9 O34 )2 Fe4 (H2 O)2 ](10-) (Fe6 W18 ) has been incorporated by direct or post-synthetic approaches into a biopolymer gelatin (Gel) matrix and two crystalline metal-organic frameworks (MOFs), including one diamagnetic (UiO-67) and one magnetic (MIL-101(Cr)). Integrity of the POM in the Fe6 W18 @Gel, Fe6 W18 @UiO-67 and Fe6 W18 @MIL-101(Cr) composites was confirmed by a set of complementary techniques. Magnetic studies indicate that the POMs are magnetically well isolated. Remarkably, in Fe6 W18 @Gel, the SMM properties of the embedded molecules are close to those of the crystals, with clear quantum tunneling steps in the hysteresis loops. For the Fe6 W18 @UiO-67 composite, the molecules retain their SMM properties, the energy barrier being slightly reduced in comparison to the crystalline material and the molecules exhibiting a tunneling rate of magnetization significantly faster th...
Journal of the American Chemical Society, Apr 27, 2016
Single-molecule magnets (SMMs) with a large spin reversal barrier have been recognized to exhibit... more Single-molecule magnets (SMMs) with a large spin reversal barrier have been recognized to exhibit slow magnetic relaxation that can lead to a magnetic hysteresis loop. Synthesis of highly stable SMMs with both large energy barriers and significantly slow relaxation times is challenging. Here, we report two highly stable and neutral Dy(III) classical coordination compounds with pentagonal bipyramidal local geometry that exhibit SMM behavior. Weak intermolecular interactions in the undiluted single crystals are first observed for mononuclear lanthanide SMMs by micro-SQUID measurements. The investigation of magnetic relaxation reveals the thermally activated quantum tunneling of magnetization through the third excited Kramers doublet, owing to the increased axial magnetic anisotropy and weaker transverse magnetic anisotropy. As a result, pronounced magnetic hysteresis loops up to 14 K are observed, and the effective energy barrier (Ueff = 1025 K) for relaxation of magnetization reached...
Inorganic Chemistry, 2009
European Journal of Inorganic Chemistry, 2014
ABSTRACT 2-Amino-4-(2-pyridyl)thiazole (H2L) complexes of iron(III), iron(II), cobalt(II), nickel... more ABSTRACT 2-Amino-4-(2-pyridyl)thiazole (H2L) complexes of iron(III), iron(II), cobalt(II), nickel(II) and copper(II) have been prepared for the first time. The oxido-bridged dinuclear ferric complex [(H2L)2FFeIII(μ-O)FeIIIF(H2L)2](BF4)2 (1) and the mononuclear difluorido complex [FeIII(H2L)2F2](BF4) (2) were prepared with Fe(BF4)2·6H2O. Complex 1 contains strong antiferromagnetically coupled iron(III) ions. In addition, the mononuclear 3:1-type complex [Co(H2L)3](ClO4)2 (3) and the mononuclear 2:1-type complexes [Cu(H2L)2](ClO4)2 (4) and [M(H2L)2(NCX)2] (5: M = Fe, X = S; 6: M = Fe, X = Se; 7: M = Co, X = S; 8: M = Ni, X = S) were prepared.
Layfield/Lanthanides and Actinides in Molecular Magnetism, 2015
Chemistry - A European Journal, 2015
Ad isk-shaped [Fe III 7 (Cl)(MeOH) 6 (m 3-O) 3 (m-OMe) 6 (PhCO 2) 6 ]Cl 2 complex with C 3 symmet... more Ad isk-shaped [Fe III 7 (Cl)(MeOH) 6 (m 3-O) 3 (m-OMe) 6 (PhCO 2) 6 ]Cl 2 complex with C 3 symmetryh as been synthesised and characterised.T he central tetrahedralF e III is 0.733 a bove the almost co-planar Fe III 6 wheel,t ow hichi t is connected through three m 3-oxide bridges.F or this ironoxo core, the magnetic susceptibility analysisproposed aHeisenberg-Dirac-van Vleck (HDvV) mechanism that leads to an intermediate spin ground state of S = 7/2 or 9/2. Within either of these grounds tate manifolds it is reasonable to expect spin frustratione ffects. The 57 Fe Mçssbauer (MS) analysis verifies that the central Fe III ione asily aligns its magnetic momenta ntiparallel to the externallya ppliedfield direction, whereast he other six peripheral Fe III ions keep their momentsa lmost perpendicular to the field at strongerf ields. This unusual canted spin structure reflects spin frustration. The small linewidths in the magnetic Mçssbauer spectra of polycrystallinesamplesc learlysuggesta nisotropic exchange mechanism for realisation of this peculiar spin topology.
Inorganic Chemistry, 2015
Reactions of the N-substituted diethanolamine ligand N-n-butyldiethanolamine with chromium(II) an... more Reactions of the N-substituted diethanolamine ligand N-n-butyldiethanolamine with chromium(II) and lanthanide(III)/rare earth salts (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y) in the presence of coligands give access to three series of isostructural 1:1 3d(Cr(III))/4f(Ln(III)) coordination cluster compounds that can be designated in terms of octanuclear "square-in-square" (Ln = La-Tb), hexanuclear "triangle-in-triangle" (Ln = Dy, Ho, Y) and tetranuclear "butterfly" or defect dicubane core (Ln = Er-Lu) topologies as revealed by single-crystal X-ray crystallographic analysis. The bulk magnetic properties were also measured. The influences of the various components in the reaction system on the final topology and the role of the ionic radius are discussed.
Rsc Advances, 2013
ABSTRACT The synthesis, structural characterization, magnetic and catalytic properties of a new c... more ABSTRACT The synthesis, structural characterization, magnetic and catalytic properties of a new class of lanthanide-containing cationic heteropolyoxovanadium clusters with a nanochocolate-like structure are reported. The title 10 compounds were characterized by single-crystal and powder X-ray diffraction, IR and 51 V-NMR spectroscopies and magnetic susceptibility measurements.
European Journal of Inorganic Chemistry, 2014
ABSTRACT A series of 2,6-bis(hydroxymethyl)-4-R-phenol ligands (H3LR; R = H, F, Cl, Br, I, Ph, NH... more ABSTRACT A series of 2,6-bis(hydroxymethyl)-4-R-phenol ligands (H3LR; R = H, F, Cl, Br, I, Ph, NH2, NO2, SMe) have either been newly synthesized or the existing syntheses have been significantly improved to investigate ligand-functionalized analogues of the previously published coordination cluster [MnIII12MnII7(μ4-O)8(μ3-N3)8(HLMe)12(MeCN)6]Cl2·10MeOH·MeCN (1) with S = 83/2. The crystal structures and magnetic properties of three such Mn19 clusters, namely, [MnIII12MnII7(μ4-O)8(HLH)12(μ3-Cl)7(μ3-OMe)(MeOH)6]Cl2·16H2O·10MeOH·MeCN (3), [MnIII12MnII7(μ4-O)8(HLI)12(μ3-N3)8(MeOH)6](O2CH)2·16MeOH·10MeCN (4) and [MnIII12MnII7(μ4-O)8(μ3-Cl)7.7(μ3-OMe)0.3(HLSMe)12(MeOH)6]Cl2·27MeOH (5) are reported and compared to those of the parent cluster. When these ligands are functionalized with substituents of moderate electronegativity, it is possible to synthesize Mn19 analogues; however, when such ligands bear highly electron-donating (amino) or -withdrawing (nitro) substituents, the Mn19 analogues are no longer accessible. The Mn19 cluster framework is both magnetically and structurally robust with respect to the electron-donor/acceptor characteristics of the ligand substituent; therefore, the Mn19 system is an excellent platform for peripheral chemical engineering.
Inorganic Chemistry, 2014
Eleven new mononuclear manganese(III) complexes prepared from two hexadentate ligands, L1 and L2,... more Eleven new mononuclear manganese(III) complexes prepared from two hexadentate ligands, L1 and L2, with different degrees of steric bulk in the substituents are reported. L1 and L2 are Schiff bases resulting from condensation of N,N'-bis(3-aminopropyl)ethylenediamine with 3-methoxy-2-hydroxybenzaldehyde and 3-ethoxy-2-hydroxybenzaldehyde respectively, and are members of a ligand series we have abbreviated as R-Sal2323 to indicate the 323 alkyl connectivity in the starting tetraamine and the substitution (R) on the phenolate ring. L1 hosts a methoxy substituent on both phenolate rings, while L2 bears a larger ethoxy group in the same position. Structural and magnetic properties are reported in comparison with those of a previously reported analogue with L1, namely, [MnL1]NO3, (1e). The BPh4(-) and PF6(-) complexes [MnL1]BPh4, (1a), [MnL2]BPh4, (2a), [MnL1]PF6, (1b'), and [MnL2]PF6, (2b), with both ligands L1 and L2, remain high-spin (HS) over the measured temperature range. However, the monohydrate of (1b') [MnL1]PF6·H2O, (1b), shows gradual spin-crossover (SCO), as do the ClO4(-), BF4(-), and NO3(-) complexes [MnL1]ClO4·H2O, (1c), [MnL2]ClO4, (2c), [MnL1]BF4·H2O, (1d), [MnL2]BF4·0.4H2O, (2d), [MnL1]NO3, (1e), and [MnL2]NO3·EtOH, (2e). The three complexes formed with ethoxy-substituted ligand L2 all show a higher T1/2 than the analogous complexes with methoxy-substituted ligand L1. Analysis of distortion parameters shows that complexes formed with the bulkier ligand L2 exhibit more deformation from perfect octahedral geometry, leading to a higher T1/2 in the SCO examples, where T1/2 is the temperature where the spin state is 50% high spin and 50% low spin. Spin state assignment in the solid state is shown to be solvate-dependent for complexes (1b) and (2e), and room temperature UV-visible and NMR spectra indicate a solution-state spin assignment intermediate between fully HS and fully low spin in 10 complexes, (1a)-(1e) and (2a)-(2e).
Supramolecular Chemistry, 2012
A systematic investigation into the coordination chemistry of Mn salicylates is presented reveali... more A systematic investigation into the coordination chemistry of Mn salicylates is presented revealing the influence on the shape and dimensionality of the final products of base, the presence or absence of co-ligands and the substituents on the salicylates. We report the synthesis, structures, characterisation and magnetic properties of seven compounds, (NHEt3)[Mn(3-MeOsal)2(MeOH)(H2O)] (1), [NaMn(3-MeO-sal)2(MeOH)2] (2), [NaMn(sal)2(H2O)(MeOH)] · (MeOH) (3), [KMn(sal)2(H2O)(MeOH)] · (MeOH) (4), [MnMn 2(3-MeOsal)4(py)6(H2O)2] · 4H2O,
Inorganica Chimica Acta, 2010
The dinickel (II) compound [Ni2 (μ-OAc) 2 (OAc) 2 (μ-H2O)(asy· dmen) 2]· 2.5 H2O, 1; undergoes fa... more The dinickel (II) compound [Ni2 (μ-OAc) 2 (OAc) 2 (μ-H2O)(asy· dmen) 2]· 2.5 H2O, 1; undergoes facile reaction in a 1: 2 molar ratio with benzohydroxamic acid (BHA) in ethanol to give the novel nickel (II) tetranuclear hydroxamate complex [Ni4 (μ-OAc) 3 (μ-BA) 3 (asy ...