Free Electron Value Research Articles

Synthesis, characterization and anti-tubercular activities of copper(II) complexes of substituted 2,3-isatin bisthiosemicarbazones: An experimental and theoretical approach

Copper(II) acetate reacted with 2,3-isatin bisthiosemicarbazone (2,3 H2bitsc), 2,3-isatin bis-N1-methyl thiosemicarbazone (2,3 H2bitsc-N1-Me) and 2,3-isatin N1-phenyl thiosemicarbazone (2,3 H2bitsc-N1-Ph) in 1:1 (M: L) to form complexes of formula, [Cu(L)] (L = 2,3 bitsc 1, 2,3 bitsc-N1-Me 2, 2,3 bitsc-N1-Ph 3). The formation of bisthiosemicarbazone ligands and their complexes are supported by elemental analysis, FTIR, NMR (1H and 13C), ESR, and Mass. For complexes 1–3, two g values obtained are: g‖ = 2.24 (1), 2.17 (2), 2.26 (3) and g⊥ = 2.09 (1), 2.11 (2), 2.08 (3) which confirm axial symmetry. The square planar geometry is confirmed from higher g‖ values than g⊥ and presence g value of free electron in dx2-y2 ground term. Ligand to metal binding ratio of 1:1 is confirmed using UV–visible spectroscopy. The ligands (2,3 H2bitsc, 2,3 H2bitsc-N1-Me and 2,3 H2bitsc-N1-Ph) and complexes (1–3) were assessed for anti-tubercular (M. tuberculosis H37RV strain ATCC27294) and antibacterial (against E. coli and S. aureus) activities. The anti- tuberculosis activity of ligands (50 µg/mL-2,3 H2bitsc, 100 µg/mL-2,3 H2bitsc-N1-Me and H2bitsc-N1-Ph) gets enhanced on complexation with copper (25 µg /mL-1, 50 µg/mL 2 and 3). The minimal binding energies calculated through molecular modeling with mycobacterium tuberculosis enoyl reductase (PDB ID: 2H7M) is −7.6 (2,3 H2bitsc), −7.3 (2,3 H2bitsc-N1-Me), −9.6 (2,3 H2bitsc-N1-Ph), −8.7 (1), −8.9 (2), and −10.7 (3) Kcal/mol. Higher negative binding energy indicates more stabilized structure in the docked state for 1–3 which supports the experimental data. The drug-protein binding study with human serum albumin (HSA) was used to explore effective transport of molecules to their target sites in 2,3 H2bitsc and its complex 1. A high binding constant of complex 1 (6.09 × 105 M−1) with respect to the ligand 2,3 H2bitsc (4.90 × 105 M−1) indicates its strong binding affinities with HSA.

EPR study of intrinsic defects within NaYGeO4 olivine

An intense electron paramagnetic resonance (EPR) spectrum has been unexpectedly observed at room temperature in polycrystalline samples of NaYGeO4 with olivine crystal structure. Signals were registered in a wide range of fields up to 6000 ​G. Along with strongly broadened unresolved resonance lines, the relatively narrow spectral components were found. It is shown that the spectrum profile depends on synthesis conditions and mechanical treatment of samples, all suggesting a partial orientational order of microcrystallites in the powders. The spectra are interpreted under the assumption of strong superhyperfine interaction between the oxygen-deficient centers like [GeO3]3- and the nuclei of Na+ cations. In addition, a sharp anisotropic resonance at g-values exceeding free-electron value is attributed to oxygenic-hole centers. The density functional theory (DFT) calculations are employed for the estimation of the thermodynamic stability of various intrinsic defects.

A brightly emissive halomanganates(II) with triphenylphosphonium cation: Synthesis, luminescence, and up-conversion phenomena

A series of [HL]2[MnX4] [X = I, Br, Cl] tetrahalomanganates with triphenylphosphonium cation has been designed and investigated in photophysics and EPR terms. At room temperature, the solid complexes exhibit a remarkably bright green phosphorescence (λmax = 525 nm–555 nm) resulted from the Mn(II) d-d transitions (4T1 → 6A1) with high quantum efficiency (>50%) and a short lifetime of the iodomanganate complex (≈41 μs). Under infrared excitation (λEx = 780 nm) the complexes exhibit unusually luminescence in the visible region (λmax ≈ 500 nm). The EPR spectra of complexes are characterized by the deviation of the g-factor from the ge free electron value and by the high value of the zero-field splitting parameters on account of the spin-orbit coupling. The correlations between the luminescence and magnetic properties of the title complexes are discussed.

A family of brightly emissive homo- and mixed-halomanganates(II): The effect of halide on optical and magnetic properties

A series of homo- and mixed-halide Mn(II) complexes of (MMTP)2[MnX4] [X = I, Br, Cl; MMTP is 1-methyl-2-(methylthio)pyridin-1-ium] and (MMTP)2[MnI2X2] types [X = Br, Cl] has been synthesized and studied in terms of photoluminescent and EPR spectroscopies. At ambient temperature, the complexes obtained in the solid state exhibit an bright green phosphorescence stemmed from the Mn(II)-centered d-d transitions (4T1 → 6A1). The homohalide complexes, (MMTP)2[MnX4], have a quantum yield of luminescence (and lifetime) of 83% (38 μs), 100% (270 μs), and 44% (2850 μs) at 300 K for X = I, Br, and Cl, respectively. Owing to iodide-enhanced spin-orbital coupling in [MnI2X2]2- anion, the phosphorescence quantum efficiency increases and is close to unity; whereas lifetime significantly decreases and is unusually short (54–64 μs). Except for (MMTP)2[MnCl4], the EPR spectra of the obtained complexes are characterized by the significant deviation of the g-factor from the ge free-electron value and by the high value of the zero-field splitting parameters on account of the spin-orbit coupling. The correlations between the luminescence and magnetic properties of the title complexes are discussed.

EPR study of NO radicals encased in modified open C60 fullerenes.

Using pulsed electron paramagnetic resonance (EPR) techniques, the low-temperature magnetic properties of the NO radical being confined in two different modified open -derived cages are determined. It is found that the smallest principal value , being assigned to the axis of the radical, deviates strongly from the free electron value. This behaviour results from partial compensation of the spin and orbital contributions to the value. The measured values in the range of 0.7 yield information about the deviation of the locking potential for the encaged NO from axial symmetry. The estimated 17 meV asymmetry is quite small compared to the situation found for the same radical in polycrystalline or amorphous matrices ranging from 300 to 500 meV. The analysis of the temperature dependence of spin relaxation times resulted in an activation temperature of about 3 K, assigned to temperature-activated motion of the NO within the modified open -derived cages with coupled rotational and translational degrees of freedom in a complicated three-dimensional locking potential.

Fermi surface of PtCoO2 from quantum oscillations and electronic structure calculations

The delafossite series of layered oxides include some of the highest conductivity metals ever discovered. Of these, PtCoO2, with a room temperature resistivity of 1.8 microOhmcm for in-plane transport, is the most conducting of all. The high conduction takes place in triangular lattice Pt layers, separated by layers of Co-O octahedra, and the electronic structure is determined by the interplay of the two types of layer. We present a detailed study of quantum oscillations in PtCoO2, at temperatures down to 35 mK and magnetic fields up to 30 T. As for PdCoO2 and PdRhO2, the Fermi surface consists of a single cylinder with mainly Pt character, and an effective mass close to the free electron value. Due to Fermi-surface warping, two close-lying high frequencies are observed. Additionally, a pronounced difference frequency appears. By analysing the detailed angular dependence of the quantum-oscillation frequencies, we establish the warping parameters of the Fermi surface. We compare these results to the predictions of first-principles electronic structure calculations including spin-orbit coupling on Pt and Co and on-site correlation U on Co, and hence demonstrate that electronic correlations in the Co-O layers play an important role in determining characteristic features of the electronic structure of PtCoO2.

Electrical and thermal conductivities of polycrystalline platinum nanowires

Understanding the electrical and thermal transport properties of polycrystalline metallic nanostructures is of great interest for applications in microelectronics. In view of the diverse experimental results in polycrystalline metallic nanowires and nanofilms, it is a long-standing question whether their electrical and thermal properties can be well predicted by a practical model. By eliminating the effects of electrical and thermal contact resistances, we measure the electrical and thermal conductivities of three different polycrystalline Pt nanowires. The electron scattering at the surface is found to be diffusive, and the charge reflection coefficient at grain boundaries is proved to be a function of the melting point. The Lorenz number is observed to be suppressed from the free-electron value by about 30%, which can be explained by introducing a thermal reflection coefficient in calculating the thermal conductivity to account for the small angle scattering effect involving phonons at the grain boundaries. Using this model, both the electrical and thermal conductivities of the polycrystalline Pt nanowires are calculated at different diameters and temperatures.

Electron spin resonance in a 2D system at a GaN/AlGaN heterojunction

Spin resonance of a two-dimensional electron system confined in a GaN/AlGaN heterostructure grown by molecular beam epitaxy was resistively detected over a wide range of magnetic field and microwave frequency. Although the spin-orbit interaction is strong in this type of heterostructure at zero magnetic field, surprisingly the width of the detected spin resonance line was very narrow—down to 6.5 mT at 13.3 T. The spin depolarization time extracted from the resonance linewidth was estimated to be 2 ns. The electron g-factor was measured with high accuracy, resembling a value close to the free-electron value and its dependence on the magnetic field was studied.

Coordination chemistry of a redox non-innocent NHC bis(phenolate) pincer ligand with nickel(II)

The electrochemical properties of the neutral nickel(II) complexes of two NHC bis(di-tert-butylphenolate) pincer ligands, namely 1 and 2, are reported. Complex 1 shows a reversible redox wave at 0.10 V vs Fc+/Fc, which corresponds to the oxidation of the phenolate moiety. The complex 1+ SbF6− was prepared and structurally characterized. The nickel ion lies in a square planar geometry identical to that observed for 1, with contracted NiO bond distances. Complex 1+ exhibits a remarkable absorption band in the NIR region, 6370 cm−1 (13,450 M−1 cm−1), assigned to a charge transfer transition associated with the radical moiety. A band shape analysis supports its classification as a mixed-valent (Class II/III) compound. Complex 1+ exhibits a resonance in the EPR spectrum at giso = 2.056, as expected for a paramagnetic (S = ½) system. The shift from the free electron value suggests the participation of a nickel d-orbital in the SOMO. DFT calculations support the mainly radical character of 1+, but show that the spin density is shared between the metal center, which harbours a spin of 0.28, and both phenolic rings of the ligand. The carbene linker does not demonstrate any significant spin population.

Resistance switching of La doped SrTiO3 single crystals

To date, there has not been a consensus about the resistance switching mechanism of donor-doped SrTiO3. The La doped STO (LaSTO) single crystal is a donor-doped material and has an N-type conductivity since La3+ could easily substitute Sr2+. In this study, the Pt/LaSTO/In memory device is fabricated based on (100) LaSTO single crystal with 0.5 wt% La doping. Through a series of electrical tests, it is found that the Pt/LaSTO/In memory device has a stable multi-stage resistive switching property, and the maximum switching ratio is 104. The fitting I-V curve at the high resistance state (HRS) shows that there is an interface barrier in the memory device. However, the fitting I-V curve at low resistance state (LRS) is consistent with the characteristic of the electron tunneling model. The spectrum of electron paramagnetic resonance (EPR) indicates that LaSTO single crystal has only one EPR signal of g=2.012. Considering the fact that g=gobs-ge (where gobs is the g factor obtained from the sample, ge=2.0023 is the free electron value) is positive, the signal can be regarded as being due to hole center. The hole center is positively charged and can trap electrons. Comprehensive analysis indicates that the transition between the HRS and LRS of the device can be explained by the modulation of Pt/LaSTO interface barrier, which is caused by the electron trapping and detrapping of interfacial vacancy defects. In addition, it is found that illumination could reduce the low resistance of the Pt/LaSTO/In device. This is due to the photo-generated carriers causing a tunneling current because of the narrow Schottky barrier when the Pt/LaSTO/In device is in the LRS. However, the Schottky barrier plays a leading role in HRS, so the change in carrier concentration, caused by illumination, does not lead to a significant change in current for HRS. The experimental results provide theoretical and technical guidance for the applications of LaSTO single crystals in resistive memory devices.

EPR/ENDOR and Theoretical Study of the Jahn–Teller-Active [HIPTN3N]MoVL Complexes (L = N–, NH)

The molybdenum trisamidoamine (TAA) complex [Mo] {[3,5-(2,4,6-i-Pr3C6H2)2C6H3NCH2CH2N]Mo} carries out catalytic reduction of N2 to ammonia (NH3) by protons and electrons at room temperature. A key intermediate in the proposed [Mo] nitrogen reduction cycle is nitridomolybdenum(VI), [Mo(VI)]N. The addition of [e-/H+] to [Mo(VI)]N to generate [Mo(V)]NH might, in principle, follow one of three possible pathways: direct proton-coupled electron transfer; H+ first and then e-; e- and then H+. In this study, the paramagnetic Mo(V) intermediate {[Mo]N}- and the [Mo]NH transfer product were generated by irradiating the diamagnetic [Mo]N and {[Mo]NH}+ Mo(VI) complexes, respectively, with γ-rays at 77 K, and their electronic and geometric structures were characterized by electron paramagnetic resonance and electron nuclear double resonance spectroscopies, combined with quantum-chemical computations. In combination with previous X-ray studies, this creates the rare situation in which each one of the four possible states of [e-/H+] delivery has been characterized. Because of the degeneracy of the electronic ground states of both {[Mo(V)]N}- and [Mo(V)]NH, only multireference-based methods such as the complete active-space self-consistent field (CASSCF) and related methods provide a qualitatively correct description of the electronic ground state and vibronic coupling. The molecular g values of {[Mo]N}- and [Mo]NH exhibit large deviations from the free-electron value ge. Their actual values reflect the relative strengths of vibronic and spin-orbit coupling. In the course of the computational treatment, the utility and limitations of a formal two-state model that describes this competition between couplings are illustrated, and the implications of our results for the chemical reactivity of these states are discussed.

Synthesis and characterization of Mn2+ doped CdOZn3(PO4)2 nanocomposites

Undoped and Mn2+ doped CdOZn3(PO4)2 nanocomposites are fruitfully synthesized by chemical precipitation process at room temperature. The morphology, structure and spectroscopic properties of the prepared samples are characterized by X-ray diffraction (XRD), optical absorption, Scanning electron microscope (SEM) with EDS, Fourier transform infrared (FT-IR) spectroscopy, Photolumiscence (PL) and Electron Paramagnetic Resonance (EPR). XRD data confirms the cubic phase of CdO and monoclinic phase of Zn3(PO4)2. Strain and dislocation density are also calculated from XRD studies. Optical absorption spectrum of Mn2+ doped CdOZn3(PO4)2 nanocomposite shows different spin-forbidden DMSO-d6 bands which are the characteristics of octahedral site symmetry related to Mn2+. The crystal field parameter Dq and inter electronic repulsion parameters (B and C) are deliberate using optical absorption data. Surface morphology of sample is firm by Using Scanning electron microscopy (SEM) and the distribution of Zn, Cd, phosphate and oxygen species in the prepared sample is identified by EDS. PL studies recognize the white light emission. The ‘g’ value of the nanocomposite material synthesized is lesser than (negative shift) the free electron value (2.0023), which gives ionic nature to the bonding and confirms the presence of Mn2+ in distorted octahedral site symmetry.

High-frequency behavior of FeN thin films fabricated by using reactive sputtering

We investigated high-frequency behavior of FeN thin films prepared by reactive sputtering through ferromagnetic resonance (FMR) and its relationship with the static magnetic properties. The FMR was observed in the frequency range from 2 to 18 GHz in the FeN films fabricated at proper nitrogen flow rate (NFR). In those FeN thin films, a decrease of the saturation magnetization and the corresponding decrease of the FMR frequency were observed as NFR was increased during the deposition. The external field dependences of the FMR frequencies were well fit to the Kittel formula and the Land\'e g-factors determined from the fit were found to be very close to the free electron value. The high-field damping parameters were almost insensitive to the growth condition of NFR. However, the low-field damping parameters exhibited high sensitivity to NFR very similar to the dependence of the hard-axis coercivity on NFR, suggesting that extrinsic material properties such as impurities and defect structures could be important in deciding the low-field damping behavior.

Research on the g factors of Cr3+ ion in elpasolite crystals Cs2NaYX6 (X = Cl, Br)

The g factors of Cr3+ ions at the cubic octahedral Y3+ sites of elpasolite crystals Cs2NaYX6(X=Cl, Br) are computed from the high-order perturbation formula founded on the two-mechanism model. In the model, both the contribution from the crystal-field (CF) mechanism in the vastly-applied CF theory and that from the frequently-omitted charge-transfer (CT) mechanism are taken into account. The parameters used in the calculations are acquired from the first-principles calculations and experiment. The calculated results are in rational accordance with the observed values. The negative g-shift Δg (=g−ge, where ge≈2.0023, the g value of free electron) for Cs2NaYCl6:Cr3+ and the positive g-shift Δg for Cs2NaYBr6:Cr3+ are therefore explained. The reasonableness of the above calculated formula and the parameters used are confirmed.

G-factors of conduction electrons and holes inBi2Se3three-dimensional topological insulator

Bulk-related conduction electron spin resonance and conduction hole spin resonance were investigated in $\mathrm{B}{\mathrm{i}}_{2}\mathrm{S}{\mathrm{e}}_{3}$, a three-dimensional topological insulator. Electrons in the conduction band and holes in the valence band both have spin \textonehalf{}. The effective $g$-factors for conduction electrons are equal to 27.3 \ifmmode\pm\else\textpm\fi{} 0.15 for magnetic field parallel to the c axis and 19.48 \ifmmode\pm\else\textpm\fi{} 0.07 for magnetic field perpendicular to the c axis, whereas for conduction holes 29.90 \ifmmode\pm\else\textpm\fi{} 0.09 for magnetic field parallel and 18.96 \ifmmode\pm\else\textpm\fi{} 0.04 for magnetic field perpendicular to the c axis, respectively. Nonparabolicity effects were not observed in the investigated low carrier concentration range, below $8\ifmmode\times\else\texttimes\fi{}{10}^{17}\phantom{\rule{0.28em}{0ex}}\mathrm{c}{\mathrm{m}}^{\ensuremath{-}3}$. Large $g$-factors, higher by an order of magnitude than the free electron value, are due to strong spin-orbit interactions in $\mathrm{B}{\mathrm{i}}_{2}\mathrm{S}{\mathrm{e}}_{3}$. The striking similarity of the spin resonances due to conduction electrons and holes confirms the peculiar symmetry between the conduction and valence bands of $\mathrm{B}{\mathrm{i}}_{2}\mathrm{S}{\mathrm{e}}_{3}$, both having similar effective masses and spin character.

Thermal and electrical conductivity of approximately 100-nm permalloy, Ni, Co, Al, and Cu films and examination of the Wiedemann-Franz Law

We present measurements of thermal and electrical conductivity of polycrystalline permalloy (Ni-Fe), aluminum, copper, cobalt, and nickel thin films with thickness $l200$ nm. A micromachined silicon-nitride membrane thermal-isolation platform allows measurements of both transport properties on a single film and an accurate probe of the Wiedemann--Franz (WF) law expected to relate the two. Through careful elimination of possible effects of surface scattering of phonons in the supporting membrane, we find excellent agreement with WF in a thin Ni-Fe film over nearly the entire temperature range from 77 to 325 K. All other materials studied here deviate somewhat from the WF prediction of electronic thermal conductivity with a Lorenz number, $L$, suppressed from the free-electron value by $10%\phantom{\rule{4.pt}{0ex}}\text{to}\phantom{\rule{4.pt}{0ex}}20%$. For Al and Cu we compare the results to predictions of the theoretical expression for the Lorenz number as a function of $T$. This comparison indicates two different types of deviation from expected behavior. In the Cu film, a higher than expected $L$ at lower $T$ indicates an additional thermal conduction mechanism, while at higher $T$ lower than expected values suggests an additional inelastic scattering mechanism for electrons. We suggest the additional low-$T\phantom{\rule{4pt}{0ex}}L$ indicates a phonon contribution to thermal conductivity and consider increased electron-phonon scattering at grain boundaries or surfaces to explain the high-$T$ reduction in $L$.

Tricritical wings in UGe2: A microscopic interpretation

In the present work we analyze the second order transition line that connects the tricritical point and the quantum critical ending point on the temperature–magnetic-field plane in UGe2. For the microscopic modeling we employ the Anderson lattice model recently shown to provide a fairly complete description of the full magnetic phase diagram of UGe2 including all the criticalities. The shape of the so-called tricritical wings, i.e. surfaces of the first-order transitions, previously reported by us to quantitatively agree with the experimental data, is investigated here with respect to the change of the total filling and the Landé factor for f electrons which can differ from the free electron value. The analysis of the total filling dependence demonstrates sensitivity of our prediction when the respective positions of the critical ending point at the metamagnetic transition and tricritical point are mismatched as compared to the experiment.

Dynamic polarizability of Rydberg atoms: Applicability of the near-free-electron approximation, gauge invariance, and the Dirac sea

Ponderomotive energy shifts experienced by Rydberg atoms in optical fields are known to be well approximated by the classical quiver energy of a free electron. We examine such energy shifts quantum mechanically and elucidate how they relate to the ponderomotive shift of a free electron in off-resonant fields. We derive and evaluate corrections to the ponderomotive free electron polarizability in the length and velocity (transverse or Coulomb) gauges, which agree exactly as mandated by the gauge invariance. We also show how the free electron value emerges from the Dirac equation through summation over the Dirac sea states. We find that the free-electron AC Stark shift comes as an expectation value of a term proportional to the square of the vector potential in the velocity gauge. On the other hand, the same dominant contribution can be obtained to first order via a series expansion of the exact energy shift from the second order perturbation theory in the length gauge. Finally, we numerically examine the validity of the free-electron approximation. The correction to the free-electron value becomes smaller with increasing principal quantum number, and it is well below a per cent for 60s states of Rb and Sr away from the resonances.

Infrared spectroscopic and electron paramagnetic resonance studies on Dy substituted magnesium ferrite

Dysprosium substituted magnesium ferrite with composition MgDyxFe2−xO4 with 0.00≤x≤0.07 synthesized by the solid state reaction technique was subjected to Fourier transform infrared spectroscopy and electron paramagnetic resonance studies. Infrared spectrum analysis were carried out to confirm the spinel phase formation and to ascertain the cation distribution in the ferrite phase. The absorption spectra show two significant absorption bands between 400 and 1000cm−1 which are attributed to tetrahedral (A) and octahedral (B) sites of the spinel phase. The positions of bands were found to be composition dependent. Splitting of bands as well as appearance of shoulders shows the presence of Fe2+ ions in the system. The force constants for tetrahedral and octahedral sites were calculated and found to vary with Dy3+ ions content. Electron paramagnetic resonance spectra of these samples exhibit broad, asymmetric resonance signal due to Fe3+/Dy3+ ions present in the host lattice. The spectra become broader with Dy3+ ions substitution in pure Mg-ferrite and this broadening is attributed to surface spin disorder (spin frustration) possibly coming from mainly antiferromagnetic interactions between the neighbouring spins in the magnetic grains. The weak superexchange interactions results in the broadening of the resonance line width and large g-value as compared to the free electron value.

Synthesis, Structural and Magnetic Properties of Ternary Complexes of (Me4P+)·{[Fe(I)Pc(−2)]−}·Triptycene and (Me4P+)·{[Fe(I)Pc(−2)]−}·(N,N,N′,N′-Tetrabenzyl-p-phenylenediamine)0.5 with Iron(I) Phthalocyanine Anions

Ternary complexes of (Me4P(+))·{[Fe(I)Pc(-2)](-)}·TPC (1) and (Me4P(+))·{[Fe(I)Pc(-2)](-)}·(TBPDA)0.5 (2) containing iron(I) phthalocyanine anions, tetramethylphosphonium cations (Me4P(+)), and neutral structure-forming triptycene (TPC) or N,N,N',N'-tetrabenzyl-p-phenylenediamine (TBPDA) molecules have been obtained as single crystals. In contrast to previously studied ionic compounds with monomeric [(Fe(I)Pc(-2)](-) anions, the anions form coordination {[Fe(I)Pc(-2)](-)}2 dimers both in 1 and 2, in which a nitrogen atom of one phthalocyanine anion weakly coordinates to the iron(I) atom of neighboring [Fe(I)Pc(-2)](-). The Fe···N distances in the dimers are 3.08(1) and 3.12(1) Å in 1 at 280 K and 2.986(5) (100 K) and 3.011(5) Å (180 K) in 2. The {[Fe(I)Pc(-2)](-)}2 dimers are packed in the layers in 1 arranged parallel to the ac plane and in isolated chains in 2 arranged along the a axis. Extended Hückel based calculation of intermolecular overlap integrals showed stronger and weaker π-π interactions within and between phthalocyanine dimers, respectively, both in 1 and 2. EPR signals of both complexes manifest two components. An major low-field asymmetric component is attributed to the Fe(I) atoms with the d(7) configuration. An origin minor narrow signal with g-factor close to the free-electron value (g = 2.0018-2.0035) is assigned to partial electron density transfer from the iron(I) center to the phthalocyanine macrocycle and the formation of the [Fe(II)Pc(-3)](-) species. Effective magnetic moments of the complexes of 1.69 (1) and 1.76 μB (2) correspond to the contribution of about one S = ½ spin per formula unit in accordance with low-spin state of [Fe(I)Pc(-2)](-). Negative Weiss temperatures of -7.6 K (1) and -13 K (2) in the 30-300 K range indicate antiferromagnetic interaction of spins in the phthalocyanine dimers. The multicomponent approach was previously proposed for the anionic fullerene complex formation. It also seems very promising to design and synthesize anionic phthalocyanine complexes with one- and two-dimensional macrocycle arrangements.