Directed exciton transport highways in organic semiconductors.

Exciton bandwidths and exciton transport are difficult to control by material design. We showcase the intriguing excitonic properties in an organic semiconductor material with specifically tailored functional groups, in which extremely broad exciton bands in the near-infrared-visible part of the electromagnetic spectrum are observed by electron energy loss spectroscopy and theoretically explained by a close contact between tightly packing molecules and by their strong interactions. This is induced by the donor-acceptor type molecular structure and its resulting crystal packing, which induces a remarkable anisotropy that should lead to a strongly directed transport of excitons.

Low-Dimensional Magnetism in Multivariate Copper/Zinc MOF-74 Materials Formed via Different Mechanochemical Methods.

MOF-74 is an archetypal magnetic metal-organic framework (MOF) family, with metal nodes bridged by 2,5-dioxido-1,4-benzenedicarboxylic acid (Hdobdc) and arranged into one of the simplest representations of the 1D Ising magnetic model. Recently, a novel mechano-synthetic approach opened a pathway toward a series of bimetallic multivariate (1:1) M1M2-MOF-74 materials, with the uniform distribution of metal cations in the oxometallic chains, offering a unique opportunity to investigate low-dimensional magnetism in these heterometallic MOFs. We explore here how different mechanochemical procedures affect the interaction between the metal nodes of the model system of three multivariate copper(II)/zinc(II)-MOF-74 materials, two of which were obtained through a template-controlled procedure, and the third one was obtained by recently developed mechanical MOF-alloying combined with subsequent accelerated aging.

Correction to: Optical Anisotropy and Momentum-Dependent Excitons in Dibenzopentacene Single Crystals.

[This corrects the article DOI: 10.1021/acsomega.2c01987.

Charge-Compensated N-Doped π-Conjugated Polymers: Toward both Thermodynamic Stability of N-Doped States in Water and High Electron Conductivity.

The understanding and applications of electron-conducting π-conjugated polymers with naphtalene diimide (NDI) blocks show remarkable progress in recent years. Such polymers demonstrate a facilitated n-doping due to the strong electron deficiency of the main polymer chain and the presence of the positively charged side groups stabilizing a negative charge of the n-doped backbone. Here, the n-type conducting NDI polymer with enhanced stability of its n-doped states for prospective "in-water" applications is developed.

Highly efficient modulation doping: A path toward superior organic thermoelectric devices.

We investigate the charge and thermoelectric transport in modulation-doped large-area rubrene thin-film crystals with different crystal phases. We show that modulation doping allows achieving superior doping efficiencies even for high doping densities, when conventional bulk doping runs into the reserve regime. Modulation-doped orthorhombic rubrene achieves much improved thermoelectric power factors, exceeding 20 μW m K at 80°C.

A mononuclear iron(III) complex with unusual changes of color and magneto-structural properties with temperature: synthesis, structure, magnetization, multi-frequency ESR and DFT study.

From the reaction of 2-hydroxy-6-methylpyridine (L) with iron(II) tetrafluoroborate, a new mononuclear iron(III) octahedral complex [FeL](BF) has been isolated. The color of the complex reversibly changed from red at room temperature to yellow-orange at the liquid nitrogen temperature. Magnetization measurements indicate that iron(III) in [FeL](BF) is in a high-spin state = 5/2, from room temperature to 1.

Charge Carrier Mobility Improvement in Diketopyrrolopyrrole Block-Copolymers by Shear Coating.

Shear coating is a promising deposition method for upscaling device fabrication and enabling high throughput, and is furthermore suitable for translating to roll-to-roll processing. Although common polymer semiconductors (PSCs) are solution processible, they are still prone to mechanical failure upon stretching, limiting applications in e.g.

Terahertz Magneto-Optical Excitations of the sd-Hybrid States of Lithium Nitridocobaltate Li(LiCo)N.

We report the results of the experimental and theoretical study of the magnetic anisotropy of single crystals of the Co-doped lithium nitride Li(LiCo)N with = 0.005, 0.01, and 0.

An unusual donor-acceptor system MnPc-TCNQ/F-TCNQ and the properties of the mixed single crystals of metal phthalocyanines with organic acceptor molecules.

The interaction of manganese(ii) phthalocyanine with 7,7,8,8-tetracyanoquinodimethane and its perfluoro derivative proceeds with the oxidation of Mn and the reduction of the acceptor molecules to give the first mixed single crystals of manganese(iii) phthalocyanine with TCNQ/F4-TCNQ radical anions. The crystals have unusual structures with C-Hπ interactions between the ions and their orthogonal arrangement, as well as remarkable redox properties. The charge transfer was proved by spectroscopic and magnetic studies.

A Phthalocyanine-Based Layered Two-Dimensional Conjugated Metal-Organic Framework as a Highly Efficient Electrocatalyst for the Oxygen Reduction Reaction.

Layered two-dimensional (2D) conjugated metal-organic frameworks (MOFs) represent a family of rising electrocatalysts for the oxygen reduction reaction (ORR), due to the controllable architectures, excellent electrical conductivity, and highly exposed well-defined molecular active sites. Herein, we report a copper phthalocyanine based 2D conjugated MOF with square-planar cobalt bis(dihydroxy) complexes (Co-O ) as linkages (PcCu-O -Co) and layer-stacked structures prepared via solvothermal synthesis. PcCu-O -Co 2D MOF mixed with carbon nanotubes exhibits excellent electrocatalytic ORR activity (E =0.

Magneto-structural correlations in oxalate-bridged Sr(ii)Cr(iii) coordination polymers: structure, magnetization, X-band, and high-field ESR studies.

The results of high-field electron spin resonance (HF-ESR) spectroscopy on the title 1D coordination polymers at frequencies up to 415 GHz, supported by X-ray diffraction, thermal, magnetic susceptibility, and X-band (10 GHz) ESR studies, are presented. The heterometallic compounds {SrCr(phen)(CO)}·HO (SrCrPhen) and {SrCr(bpy)(CO)(HO)}·5HO (SrCrBpy) (phen = 1,10-phenanthroline, bpy = 2,2'-bipyridine) were synthesized. Structural analysis revealed double oxalate-bridged zigzag Sr-Cr chains while magnetic susceptibility studies showed paramagnetic behaviour of the complexes.

Static and dynamic magnetic properties of the ferromagnetic coordination polymer [Co(NCS)(py)].

[Co(NCS)(py)] (py = pyridine) is composed of ferromagnetic chains of Co(ii) cations connected by double NCS bridges. The chains are irregular because of two crystallographically inequivalent Co(ii) cations. The coordination polyhedron of the Co(ii) cations is a distorted octahedron built from two N and two S atoms of four equatorial NCS anions and two apical N atoms of the pyridine ligands.

Synthesis and magnetic properties of manganese carbonyl complexes with different coordination modes of 3,4,5-triaryl-1,2-diphospholide ligands.

The set of complexes bis-(μ:η(1),η(1)-3,4,5-triaryl-1,2-diphosphacyclopentadienyl)-bis-(tetracarbonyl manganese(i)) (aryl = C6H5 (), p-FC6H4 (), p-ClC6H4 ()) undergo an irreversible rearrangement to mononuclear 3,4,5-triaryl-1,2-diphosphacymantrenes (). According to quantum-chemical calculations binuclear complexes can be considered to be products of kinetic control and mononuclear species are thermodynamically favorable compounds. The antiferromagnetic intramolecular interaction observed for complexes can be effectively tuned by using substituents in the para-position of the arene ring, whereas mononuclear 1,2-diphosphacymantrenes are diamagnetic.

Magnetic superexchange interactions: trinuclear bis(oxamidato) versus bis(oxamato) type complexes.

The diethyl ester of o-phenylenebis(oxamic acid) (opbaH2Et2) was treated with an excess of RNH2 in MeOH to cause the exclusive formation of the respective o-phenylenebis(N(R)-oxamides) (opboH4R2, R = Me , Et , (n)Pr ) in good yields. Treatment of with half an equivalent of [Cu2(AcO)4(H2O)2] or one equivalent of [Ni(AcO)2(H2O)4] followed by the addition of four equivalents of [(n)Bu4N]OH resulted in the formation of mononuclear bis(oxamidato) type complexes [(n)Bu4N]2[M(opboR2)] (M = Ni, R = Me , Et , (n)Pr ; M = Cu, R = Me , Et , (n)Pr ). By addition of two equivalents of [Cu(pmdta)(NO3)2] to MeCN solutions of , novel trinuclear complexes [Cu3(opboR2)(L)2](NO3)2 (L = pmdta, R = Me , Et , (n)Pr ) could be obtained.

Band-like electron transport with record-high mobility in the TCNQ family.

The occurrence of extremely pronounced band-like transport with very high electron mobility in fluorinated tetracyanoquinodimethane (F2 -TCNQ) single-crystal field-effect transistors is discovered. This finding identifies the Fx -TCNQ family as a paradigm to investigate the fundamental aspects of electronic transport in organic crystals.

Magnetic moments and exchange coupling in nitride clusterfullerenes Gd(x)Sc(3-x)N@C80 (x = 1-3).

The magnetic properties of nitride clusterfullerenes GdxSc3-xN@C80 (x = 1-3) are studied as a function of the number of Gd atoms in the cluster. The intracluster interaction of the Gd ions in Gd2ScN@C80 and Gd3N@C80 is ferromagnetic with exchange constants of -1.2 K ± 0.

Synthesis and toxicity characterization of carbon coated iron oxide nanoparticles with highly defined size distributions.

Background: Iron oxide nanoparticles hold great promise for future biomedical applications. To this end numerous studies on iron oxide nanoparticles have been conducted. One aspect these studies reveal is that nanoparticle size and shape can trigger different cellular responses through endocytic pathways, cell viability and early apoptosis.

Chemisorption of exchange-coupled [Ni2L(dppba)]+ complexes on gold by using ambidentate 4-(diphenylphosphino)benzoate co-ligands.

A new strategy for the fixation of redox-active dinickel(II) complexes with high-spin ground states to gold surfaces was developed. The dinickel(II) complex [Ni2L(Cl)]ClO4 (1ClO4), in which L(2-) represents a 24-membered macrocyclic hexaaza-dithiophenolate ligand, reacts with ambidentate 4-(diphenylphosphino)benzoate (dppba) to form the carboxylato-bridged complex [Ni2L(dppba)](+), which can be isolated as an air-stable perchlorate [Ni2L(dppba)]ClO4 (2ClO4) or tetraphenylborate [Ni2L(dppba)]BPh4 (2BPh4) salt. The auration of 2ClO4 was probed on a molecular level, by reaction with AuCl, which leads to the monoaurated Ni(II)2Au(I) complex [Ni(II)2L(dppba)Au(I)Cl]ClO4 (3ClO4).

A new layered triangular antiferromagnet Li4FeSbO6: spin order, field-induced transitions and anomalous critical behavior.

Structure, electrochemical, magnetic and resonance properties of new layered antimonate Li(4)FeSbO(6) were comprehensively studied using powder X-ray diffraction, cyclic voltammetry, magnetic susceptibility, heat capacity, electron spin resonance and Mössbauer spectroscopy. In the crystal structure the iron ions form the triangular network within (LiFeSbO(6))(3-) layers alternating with nonmagnetic lithium layers. The electrochemical activity studied implies an Fe(3+)/Fe(4+) redox couple at 4.

An interplay between the spin density distribution and magnetic superexchange interactions: a case study of mononuclear [(n)Bu4N]2[Cu(opooMe)] and novel asymmetric trinuclear [Cu3(opooMe)(pmdta)2](NO3)2·3MeCN.

Treatment of the diethyl ester of o-phenylenebis(oxamic acid) (opbaH(2)Et(2), 1) with 5/6 equivalent of MeNH(2) in abs. EtOH results in the exclusive formation of the ethyl ester of o-phenylene(N′-methyl oxamide)(oxamic acid) (opooH(3)EtMe, 2) in ca. 50% yield.

Evidence for triplet superconductivity in a superconductor-ferromagnet spin valve.

We have studied the dependence of the superconducting (SC) transition temperature on the mutual orientation of magnetizations of Fe1 and Fe2 layers in the spin valve system CoO(x)/Fe1/Cu/Fe2/Pb. We find that this dependence is nonmonotonic when passing from the parallel to the antiparallel case and reveals a distinct minimum near the orthogonal configuration. The analysis of the data in the framework of the SC triplet spin valve theory gives direct evidence for the long-range triplet superconductivity arising due to noncollinearity of the two magnetizations.

Slow magnetic relaxations in manganese(III) tetra(meta-fluorophenyl)porphyrin-tetracyanoethenide. Comparison with the relative single chain magnet ortho compound.

Mn(III) tetra(meta-fluorophenyl)porphyrin-tetracyanoethenide coordination polymer (abbreviated meta-F) was synthesized and crystallographically and magnetically characterized. The compound crystallizes in the space group C2/c with four equivalent molecules in the unit cell arranged along two symmetry related nonparallel linear chain directions. Magnetic properties were studied by SQUID dc magnetization and ac susceptibility techniques and high field-high frequency electron spin resonance (HF-ESR).

New dinuclear nickel(II) complexes: synthesis, structure, electrochemical, and magnetic properties.

The reaction of [NiBr(2)(bpy)(2)] (bpy = 2,2'-bipyridine) with organic phosphinic acids ArP(O)(OH)H [Ar = Ph, 2,4,6-trimethylphenyl (Mes), 9-anthryl (Ant)] leads to the formation of binuclear nickel(II) complexes with bridging ArP(H)O(2)(-) ligands. Crystal structures of the binuclear complexes [Ni(2)(μ-O(2)P(H)Ar)(2)(bpy)(4)]Br(2) (Ar = Ph, Mes, Ant) have been determined. In each structure, the metal ions have distorted octahedral coordination and are doubly bridged by two arylphosphinato ligands.