Bridged macrocyclic transition metal complexes as semiconducting materials

Hanack, Michael; Linge, A.; Rein, M.; Behnisch, R.; Renz, G.; Leverenz, Andreas

doi:10.1016/0379-6779(89)90871-0

Cited by 39 publications

(3 citation statements)

References 9 publications

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“…Similarly, three oxidation processes were observed in both DMF and DCM for the PcFe II ( n -BuNH 2 ) 2 complex with the first two processes being reversible (Table and Figure ). In agreement with the earlier reports, ,,− a single reversible oxidation wave for PcFe II Py 2 was observed in the Py/0.1 M TBAP system, which has a smaller anodic potential window (Table and Figure S6, Supporting Information). In polar media (DMA/0.1 M TPAP system), Stillman and co-workers observed two oxidation processes for this compound, and we observed three oxidation waves (with only the first process being reversible) in a DMF/0.05 M TFAB system (Figure S6, Supporting Information).…”

Section: Resultssupporting

confidence: 91%

Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

et al. 2021

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The electronic structures and, particularly, the nature of the HOMO in a series of PcFeL 2 , PcFeL′L″, and [PcFeX 2 ] 2− complexes (Pc = phthalocyaninato(2-) ligand; L = NH 3 , n-BuNH 2 , imidazole (Im), pyridine (Py), PMe 3 , PBu 3 , t-BuNC, P(OBu) 3 , and DMSO; L′ = CO; L″ = NH 3 or n-BuNH 2 ; X = NCO − , NCS − , CN − , imidazolate (Im − ), or 1,2,4triazolate(Tz − )) were probed by electrochemical, spectroelectrochemical, and chemical oxidation as well as theoretical (density functional theory, DFT) studies. In general, energies of the metal-centered occupied orbitals in various six-coordinate iron phthalocyanine complexes correlate well with Lever Electrochemical Parameter E L and intercross the phthalocyaninecentered a 1u orbital in several compounds with moderate-to-strong π-accepting axial ligands. In these cases, an oxidation of the phthalocyanine macrocycle (Pc(2-)/Pc(1-)) rather than the central metal ion (Fe(II)/Fe(III)) was theoretically predicted and experimentally confirmed.

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Section: Resultssupporting

confidence: 91%

Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

et al. 2021

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“…The on-site Coulomb energy was roughly estimated to be Uϳ1.5 eV according to the earlier experimental reports. 22,23 If one assumes the symmetric Anderson model for the simplicity, the antiferromagnetic exchange interaction Jϳ͗V͘ 2 /U between the itinerant electrons and the local moments is estimated to be of order of 60 K. 24 When one applies the field, the population of the local moments parallel to the field increases. The magnetic field disturbs the free motion of the local moments and reduces the probability of the spin-flip scattering.…”

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confidence: 99%

Giant negative magnetoresistance in quasi-one-dimensional conductorTPP[Fe(Pc)(CN)2
Hanasaki
¹
,
Tajima
²
,
Matsuda
³

et al. 2000
Phys. Rev. B
120
1
76
0
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We have found giant negative magnetoresistance in the one-dimensional conductor TPP͓Fe(Pc)(CN) 2 ͔ 2 below 50 K. The reduction of the resistance is larger in the field perpendicular to the one-dimensional axis than parallel to the axis. The magnetic susceptibility shows anisotropic Curie-Weiss behavior. The experimental results suggest the interaction between the one-dimensional electron system and the local moments. The reduction of the spin scattering of the itinerant electrons by the local moments under the field is proposed as the origin of the giant negative magnetoresistance.The interplay between conduction electrons and local magnetic moments has provided a variety of interesting phenomena such as Kondo effect, Ruderman-Kittel-KasuyaYosida interaction, heavy fermion, giant magnetoresistance, and colossal magnetoresistance. 1-5 The giant negative magnetoresistance was reported in the manganese oxides 5 and -BETS 2 FeCl 4 , 6 and is accompanied or caused by the sharp metal-insulator transition.There have been very few reports on these phenomena in the one-dimensional system, although theoretical studies predict several attractive phenomena such as Kondo effects in a Luttinger liquid. 3,7,8 Quasi-one-dimensional molecular conductors are good candidates for this research. By introducing the local moments (d electron͒ into these conductors, the interaction (-d interaction͒ between the one-dimensional conduction electrons ( electron͒ and the local moments is expected to give different electronic states. In fact, interesting phenomena such as negative magnetoresistance were reported in the one-dimensional molecular conductor ͓Cu x Ni 1Ϫx (Pc)͔(I 3 ) 1/3 , 9,10 where electron in Pc ͑ϭphthalocyanine͒ forms the conduction band and d electron in Cu 2ϩ affords the local moment. However, owing to the experimental difficulty, the systematic studies on the anisotropy of this system have not been reported. The negative magnetoresistance was also reported in the one-dimensional Peierls compounds, 11 and the critical temperature of the negative magnetoresistance decreases on increasing the magnetic-field strength.The title compound TPP͓Fe(Pc)(CN) 2 ͔ 2 and the isostructural compound TPP͓Co(Pc)(CN) 2 ͔ 2 ͑TPPϭtetraphenyl-phosphonium͒ have a one-dimensional conduction band coming from the orbital of Pc, since the partially oxidized Pc units stack uniformly along the c axis. The Fe compound has Sϭ1/2 local moments of Fe 3ϩ in the conduction path, 12 while there are no local moments in the Co compound. 13 TPP molecules and CN ligands hold closed-shell orbitals. The striking difference in the resistance behavior of these compounds was reported. 12,13 This difference suggests the possibility of the interaction between the one-dimensional conduction electrons and the local moments.The Pc molecule has a structure with fourfold symmetry and one can expect the degeneracy in the molecular orbitals of Pc. It is of great interest how this degeneracy influences the physical properties.In order to obtain the clear-cut experimental evidenc...

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“…The properties of the molecular unit may be varied by introducing substituents on the phthalocyanine ring or by extending the conjugation of the macrocycle, as in naphthalocyanines [8][9][10]. In order to get a chiral molecular semiconductor, we chose to work on 1,2-naphthalocyanine derivatives.…”

Section: Introductionmentioning

confidence: 99%

Towards chiral 1,2-naphthalocyanines: 2. Synthesis of lutetium bismacrocyclic derivatives

Negrimovskii

Bouvet

Luk'yanets

et al. 2001

J. Porphyrins Phthalocyanines

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ABSTRACT:Starting from 1,2-naphthalocyanine lutetium acetate (1,2-NcLuOAc) the unsymmetrical lutetium phthalo(naphthalo)cyanine (1,2-NcLuPc) has been synthesized and characterized by optical absorption spectra and fast atom bombardment (FAB) mass spectrometry. 1,2-Naphthalocyanine shows several geometrical isomers, both the mixture (noted Nc AE ) and one of them (Nc C S ) have been used for forming the corresponding bismacrocycles. As a result the first racemic mixture of a chiral unsubstituted phthalo(naphthalo)cyanine complex has been synthesized and characterized.

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Bridged macrocyclic transition metal complexes as semiconducting materials

Cited by 39 publications

References 9 publications

Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Giant negative magnetoresistance in quasi-one-dimensional conductorTPP[Fe(Pc)(CN)2
Hanasaki
¹
,
Tajima
²
,
Matsuda
³

et al. 2000
Phys. Rev. B
120
1
76
0
View full text Add to dashboard Cite

Towards chiral 1,2-naphthalocyanines: 2. Synthesis of lutetium bismacrocyclic derivatives

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Bridged macrocyclic transition metal complexes as semiconducting materials

Cited by 39 publications

References 9 publications

Application of Lever’s EL Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Application of Lever’s EL Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Giant negative magnetoresistance in quasi-one-dimensional conductorTPP[Fe(Pc)(CN)2Hanasaki1, Tajima2, Matsuda3 et al. 2000Phys. Rev. B1201760View full textAdd to dashboardCite

Towards chiral 1,2-naphthalocyanines: 2. Synthesis of lutetium bismacrocyclic derivatives

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Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Application of Lever’s E_L Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes

Giant negative magnetoresistance in quasi-one-dimensional conductorTPP[Fe(Pc)(CN)2
Hanasaki
¹
,
Tajima
²
,
Matsuda
³

et al. 2000
Phys. Rev. B
120
1
76
0
View full text Add to dashboard Cite