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Subglacial till can deform when overriding ice exerts shear traction at the ice--till interface. This deformation leaves a strain signature in the till, aligning grains in the direction of ice flow and producing a range of diagnostic microstructures. Constraining the conditions that produce these kinematic indicators is key to interpreting the myriad of features found in basal till deposits. Here, we used a cryogenic ring shear device with transparent sample chamber walls to slip a ring of temperate ice over a till bed from which we examined the strain signature in the till. We used cameras mounted to the side of the ring shear and bead strings inserted in the till to estimate the strain distribution within the till layer. Following the completion of the experiment, we extracted and analyzed anisotropy of magnetic susceptibility (AMS) samples and created thin sections of the till bed for microstructure analysis. We then compared the AMS and microstructures with the observed strain history to examine the relationship between kinematic indicators and strain in a setting where shear traction is supplied by ice. We found that AMS fabrics show a high degree of clustering in regions of high strain near the ice--till interface. In the uppermost zone of till, [k.sub.1] eigenvector azimuths are generally aligned with ice flow, and [S.sub.1] eigenvalues are high. However, [S.sub.1] eigenvalues and the alignment of the [k.sub.1] eigenvector with ice flow decrease nonlinearly with distance from the ice--till interface. There is a high occurrence of microshears in the zone of increased deformation. Key words: till deformation, microstructures, anisotropy of magnetic susceptibility, glacial geology, 1. Introduction Many of the world's fastest moving glaciers slip atop till beds, and the mechanics active within these beds control glacier motion (Kamb 2001) and landform development (Clark 1993). [...]

Author(s): S. Farokhipoor [1]; C. Magen (corresponding author) [2, 3]; S. Venkatesan [4]; J. Iniguez [5]; C. J. M. Daumont [1]; D. Rubi [1]; E. Snoeck [3, 6]; M. Mostovoy [...]

Exact solution of the magnetic susceptibility for an S = 1/2 defective finite Ising chain is obtained by employing the transfer matrix method. The thermal dependence of susceptibility multiplied by temperature for the chain coupled to different magnetic impurities is investigated at all T ≥ 0. The results show that in the zero temperature limit the product of these two quantities equals the square of the net spin, demonstrating that Curie's constants are truly invariant at low temperatures. The intrinsic properties of net spin are also reflected through their different responses to the parity of chain length at low temperature. In addition, the impacts of various host-impurity couplings as well as single-ion anisotropies on the susceptibility are discussed as well. PACS Nos.: 75.10.Pq, 75.30.Hx, 75.40.Cx. La methode de la matrice de transfert nous permet d'obtenir une solution exacte pour la susceptibilite d'une chaine S = 1/2 de Ising avec defauts. Nous analysons, pour tout T ≥ 0, la dependance thermique de la susceptibilite multipliee par la temperature, pour la chaine couplee a differentes impuretes magnetiques. Les resultats montrent, qu'a la limite de la temperature nulle, le produit de ces deux quantites est egal au carre du spin net, demontrant que les constantes de Curie sont de vrais invariants a basse temperature. Les proprietes intrinseques du spin net se refletent aussi dans leurs differentes reponses a la parite de la longueur de chaine a basse temperature. Nous discutons egalement les impacts sur la susceptibilite des differents couplages hote-impuretes, aussi bien que des anisotropies a un ion. [Traduit par la Redaction], 1. Introduction Low-dimensional quantum antiferromagnets have been the subject of considerable investigation in condensed matter physics because of the novel phenomena originating from their low dimensionality and strong quantum fluctuations [...]

White Mountain is centrally located in the bedding-plane portion of the Eocene Heart Mountain detachment and contains the only upper plate Mississippian Madison Group rocks that have been metamorphosed into marble. The marble rests upon the thickest (1 m) part of a carbonate ultracataclasite that marks the detachment. Thermodynamic and mechanical calculations based on possible frictional melting of calcite and other minerals, geochemical data, the characteristics of the carbonate ultracataclasite, and the geometrical characteristics of White Mountain suggest a possible initial upper plate emplacement rate of 126-340 m/sec and that the duration of the emplacement event was less than 4 min, too brief a time to develop an emplacement-related calcite twinning strain overprint in upper or lower plate carbonates. While the detachment-related carbonate ultracataclasite did not form by melting, it does preserve a magnetic fabric where [K.sub.max] is parallel to the detachment slip direction and records a westward and down paleopole (287[degrees] and 27[degrees]), where magnetite is the carrier mineral. The Eocene (49.6 Ma) paleopole for this latitude in North America was southerly and upward (0[degrees] and 45[degrees]). This brief and catastrophic detachment event produced a significant amount of C[O.sub.2] by flash heating. This report is the first to quantify the emplacement rate of the upper plate of the Heart Mountain detachment based on physical and geochemical parameters. Keywords: Heart Mountain detachment, calcite strains, paleomagnetism, thermodynamics, flash heating.

The magnetic dynamics of [Fe.sub.71] [Al.sub.29](x = 71) and [Fe.sub.70] [Al.sub.30](X = 70) are analyzed. The alloys have been prepared by milling and further annealing. AC-susceptibility has been measured from 5 K to 300 K at several frequencies between 100 and 10 kHz with an alternating field of 0.10e. In x = 70, additional susceptibility data fixing the frequency to 500 Hz and varying the field between 0.1 [less than or equal to] h [less than or equal to] 10 Oe were obtained. The results display real components similar to those reported in DC-magnetization, with two transitions in x = 70 and a single transition in x = 71. The complex component is much more clear with a well-defined peak for the low temperature transition ascribed to a spin freezing. The frequency variation gives 0.078(5) in x = 70 and critical zv = 7.2(5) and 0.066(9) and zv = 9.8(5) for x = 71, related to a cluster glass behavior. However the parameter [beta] [approximately equal to] 1 for both alloys which is high in the framework of a conventional slowing down. This is related to the clustered nature of the magnetic structure lacking of defined interfaces. Index Terms--AC-susceptibility, intermetallics, magnetic relaxation, spin-glass.

Cd[Fe.sub.2][O.sub.4] thin films have been prepared by a sputtering method, and their structural and magnetic properties have been examined. As-deposited film shows magnetic transition like that of cluster-spin glass or superspin glass, and possesses large magnetization even at room temperature. The magnetic behaviors are partly attributed to crystal structure with a random distribution of cations in Cd[Fe.sub.2][O.sub.4] nanocrystals. Annealing of the as-deposited film at 200[degrees]C leads to an increase in magnetization while the magnetization is decreased when the film is annealed at 400[degrees]C. The effect of annealing on the magnetic properties has been discussed in terms of the change of microstructure as well as chemical structure of the thin films. Index Terms--Ferrite films, magnetic susceptibility.

The article studies the separation of biological materials by using Magneto-Archimedes levitation. Results suggest that the technique is beneficial for quick and accurate separation of small amounts of biological materials.

Different methods for preparation and the enhancement of [T.sub.c], shielding and irreversibility line in argon preheated Ln(SrBa) [Cu.sub.3][O.sub.6Z] are described. The observed result is mainly due to the increase in the cationic and chain oxygen ordering in the samples.

The syntheses, crystal structures, and magnetic susceptibilities of a family of copper pyrazine (pz)-based antiferromagnets with moderate in-plane magnetic exchange is reported. The compounds are well described by the two-dimensional Heisenberg model over most of the temperature range but undergo transition to an ordered state at low temperature.

The magnetic anisotropy of a textured [Ni.sub.51.4][Mn.sub.28.3][Ga.sub.20.3] thin film, which is sputter deposited on alumina ceramic substrate, is described. A consistent procedure is developed for determining the angle of the easy-magnetic axis with respect to the film normal and the ratio between the magnetic anisotropic energy and the magnetostatic energy.

A general protocol for the structural characterization of paramagnetic molecular solids using solid-state NMR is provided and illustrated by the characterization of a high-spin [Fe.sup.II] catalyst precursor. The results include the optimization of broadband heteronuclear recoupling sequences for polarization transfer and the observation of single or multiple quantum correlation spectra between coupled spins as a tool for removing the inhomogeneous bulk susceptibility (BMS) broadening.

A modified Curie-Weiss law was proposed to analyze the anisotropic magnetic susceptibilities of [Na.sub.x]Co[O.sub.2] (x=0.75) and implications of this analysis concerning the metallic properties and the long range antiferromagnetic ordering of [Na.sub.x]Co[O.sub.2] was explored. The magnetic structures of [Na.sub.x]Co[O.sub.2] deduced from neutron scattering and magnetic susceptibility studies were shown to be in apparent contradiction.

The synthesis, structure and magnetic properties of the members of [Co[(4-terpyridone).sub.2]][X.sub.p].nS family are reported using X-ray single crystal determination and magnetic susceptibiliy studies. The rationalization of the factors that govern the spin-crossover process in cationic transition-metal complexes is difficult because they are not always consistent from one system to another, and in general, are not predictable.

The synthesis, characterization and the effects of isochronal annealing of nearly monodispersive three-dimensional arrays of Co nanoparticles are described. The synthesis technique is expected to work for other immiscible metal-ceramic systems and thus may be of technological interest in the manufacture of devices employing metallic nanoparticles.

N[d.sub80]F[e.sub.20] bulk specimens are prepared by copper mold casting and their structure and magnetic properties are studied. The saturation magnetization, the anisotropy fields, and the high-field susceptibility values of the hard magnetic Fe-Nd regions are deduced from the fits in the temperature range of 75-290 K.

Magnetic-susceptibility measurements, nuclear magnetic resonance (NMR) of (super 11)B, and electron magnetic-resonance (EMR) spectra of YCO3B2 are measured as a function of the temperature. The temperature dependence of the magnetic susceptibility reveals a lambda-shaped anomaly at 150 K.

Magnetic susceptibility, ytterbium L(sub III)-edge x-ray absorption and tin-119 Mossbauer spectral measurements have been carried out to probe the electronic structure of ytterbium and tin in the filled or partially filled skutterudite compounds, Yb(sub y)Co4Sb(sub 12-x)Sn(sub x), over a range of x and y values. The tin electronic configuration is both very similar to that of the antimony in the structure and insensitive to the ytternium, y.

An interaction mechanism was proposed to explain the influence of static magnetic fields on electrochemical processes that take place when a ferromagnetic electrode is submerged in a paramagnetic electrolytic solution. The proposed mechanism suggests that the magnetic field effect is strengthened by magnetic flux density and magnetic susceptibility of the solution and is weakened when temperature and stirring rate is decreased. The magnetoconvection phenomena suggested is supported by experimental results.

Crystals of the heterocyclic diradical benzo-1,2:4,5-bis(1,3,2-dithiazolyl) (BBDTA) were grown and characterized. X-ray crystallographic analysis revealed that the compound consists of discrete, unassociated molecules that form slipped stacks along the x direction, with the molecular plane making an angle of 32.4 degrees to the x axis. Electron resonance spectrometry showed signals characteristic of partially associated materials and free diradicals. It was also indicated by ab initio calculations that there is a small separation between the triplet and singlet diradical states, measuring approximately 0.5 kcal/mol. Magnetic susceptibility measurements indicated that BBDTA is diamagnetic.

(Carbido)decaruthenium carbonyl clusters were analyzed by electron spectroscopy, magnetic susceptibility, near infrared and electron paramagnetic resonance spectrometric studies. The results revealed that the the metal cluster compound exhibits properties that are characteristic of high-nuclearity carbonyl clusters in terms of having 'molecular' rather than 'mesometallic' character.

Anisotropy of low field magnetic susceptibility (AMS) is a versatile petrofabric tool. For magnetite, AMS primarily defines grain-shape anisotropy; for other minerals, AMS expresses crystallographic control on magnetic properties. Thus, we may infer the orientation-distribution of a dominant mineral from the AMS of a rock. AMS principal directions can record current directions from sediment, flow-directions from magma, finite-strain directions from tectonized rocks and stress-directions from low-strain, low-temperature, neotectonic environments. AMS measurements may reveal some aspects of the strain-path, where carefully selected. For example, we may compare different parts of a heterogeneously strained domain, different minerals in a homogeneously strained site, AMS with schistosity/mineral lineation, and AMS with remanence-anisotropy. Such measurements isolate the orientation-distributions of different minerals, adding a temporal scale to the kinematic sequence. Normally, we can interpret the principal directions of AMS distributions as a physically significant direction, such as a current direction, magmatic flow or finite-strain axis. However, calibrating the AMS ellipsoid shape against the magnitude of the controlling physical process is very difficult. Primarily, this is because the shape of the AMS ellipsoid combines contributions from several minerals whose individual AMS ellipsoids are of different shape. Thus, small variations in the proportions of minerals change the shape of the rock's AMS ellipsoid, even if the alignment process were of constant intensity. In deformed rocks, AMS is more strain-sensitive than calcite twinning or the alignment of calcite or quartz c-axes. Not all AMS fabrics relate to crystallographic or grain alignment. First, displacement fabrics generate AMS where an isotropic matrix of high susceptibility displaces unevenly spaced objects of low susceptibility and suitable scales. Second, AMS location fabrics occur where sub-isometric magnetite grains are close enough, in certain directions, for their demagnetizing fields to interact. This accounts for the AMS of many magnetite-dominated signals where there is no aligned magnetite. Third, the AMS of single-domain magnetite is inverse to shape so that such grains may oppose the AMS contribution of parallel minerals. Finally, transitional sedimentary-tectonic or magmatic-tectonic fabrics yield smeared, temporal sequences of AMS principal directions that cannot be immediately attributed to a single alignment process. These transitional AMS ellipsoids mix primary and secondary AMS components, making it difficult to characterize either component. However, such fabric combinations may permit us to recognize the sense of shearing in flow processes. Keywords: AMS; magnetic susceptibility; anisotropy; petrofabrics; tectonic deformation; tectonic stress; crystal or grain alignment

We report a very simple and inexpensive technique for detecting the screening of the B field by high temperature superconductors via the change in the inductance of a coil containing the sample. While related to previously reported techniques for measurement magnetic susceptibility via changes in inductance, the apparatus we report does not require lock-in amplification and is suitable for general physics labs.

The measurements of nitrogen-proton J splittings in 15N-enriched human ubiquitin are accurate to a few hundredths of a hertz but are dependent on the static magnetic field strength. This dependence may be due to a dynamic frequency shift caused by the interfering 15N chemical shift anisotropy and the 15N-1H dipolar coupling relaxation. The anisotropic magnetic susceptibility of the diamagnetic ubiquitin also contributes to the dependence. The best fit of the measured nitrogen-proton J splittings agrees exactly with theoretical predictions.

Cobalt(II)- and nickel(II)-substituted azurins from Pseudomonas aeruginosa contain distorted tetrahedral environments at the active sites with one ligand moving away from the metal center. Electronic characteristics and magnetic susceptibility of Co(II) and Ni(II)-substituted azurins are analyzed by EPR spectroscopy. The EPR spectrum of Co(II)-azurin exhibit characteristic patterns of Kramer's doublet. Ni(II)-azurin shows an effective magnetic moment of 2.8 micron(sub B).

The preparation and characterization of oxo-bridged (Cr2 tmpa2 mu-O X)n+, where tmpa = tris(2-pyridylmethyl)amine; X = CO(sub 3)(super 2-), PhPO4(super 2-), HS-, are described. The results showed a linear, empirical relationship between antiferromagnetic coupling constants and oxo bridge basicity. The crystal structure of the complex (tmpa Cry mu-O mu-CO3 Cr tmpa)(ClO4)2.2H20 has also been determined.

SQUID magnetometric studies of the magnetic susceptibility of the iron arsenate Fe2As4O12 at 5 K indicate the occurrence of long-range ordering in this compound, despite a crystal structure that favors short-range ordering. This phase consists of Fe2O(sub 9)(super 12-) dimers linked by AsO(sub 4)(super 3-). The magnetic moments are present normal to the c axis and maximum susceptibility is attained at 50 K.

A phase sensitive detector-based technique enables an assessment of the variations in magnetic susceptibility of equi-atomic CoPt alloy subjected annealing up o 850 K with atomic ordering. The Curie-Weiss law is obeyed by magnetic susceptibility in the paramagnetic region. The Co and Pt magnetizations mutually reorient, leading to maxima at 630 and 710 K, while the change in axis from (111) to (001) causes the maximum at 470 K.

A comparative study of experimental and theoretical transverse susceptibility values for isotropic and aligned samples of magnetic recording media such as gamma-Fe2O3 and barium-ferrite samples doped with ZnTi in varying remanence states indicates the interparticle reactions and dissimilar magnetization states to cause the deviations of the experimental values from the Stoner-Wohlfarth theoretical values. Interactions between the particles induce the formation of intermediary states during the process of magnetic reversal.

A study of ac-susceptibility of the intermetallic system Zr(1-x)Ho(x)Co2 with the help of a Sumitoma ac susceptometer at temperatures between 13 and 300 K indicates variations in magnetic ordering temperature (Tc) and order of magnetic transition with value of x. Tc decreases with hydrogenation and increases with an increase in value of x. The system exhibits Pauli paramagnetism at an x value of 0. Charge transfer effects cause the mitigation of exchange interactions during hydrogen absorption.

Spectroscopic analysis of cyanide-inhibited horseradish (HRP) and cytochrome c peroxidases helps understand the hyperfine shift pattern for the nonheme protons with regard to the paramagnetic susceptibility tensor. The tilt from the normal to the magnetic axis affects the hyperfine shift pattern, which varies with binding between the substrate and HRP. This tilt can be connected with the Fe-CN unit tilt and facilitates comprehension of the variations in distal interactions with the coordinated ligand.

High-spin (Mn12O12(O2CMe)16(H2O)4) reacts with EtCO2H in toluene to form (Mn12O12(O2CEt)16(H2O)3), which, upon reduction with PPh4I in CH2Cl2, forms (PPh4)(Mn12O12(O2CEt)16(H2O)4). DC studies of all the complexes reveal the existence of well-developed hysteresis loops and the presence of distinct magnetic susceptibility relaxation effects. These relaxation processes can be explained by the properties of individual molecules and not by a bulk effect of the material.

Use of the (Cu(DopnH))(+) cation, (H2Dopn is 3,9-dimethyl-4,8-diazaundeca-3,8-diene-2,10-dione dioxime) helps synthesize heterodinuclear complexes of the type Cu(II)M, (M is Cr(III), Mn(III), Mn(II), Fe(III), Co(II), Zn(II)). The synthesis reveals the ability of the oximate dianion to act as a bridging ligand and mediate of exchange interactions. Spectroscopic and variable-temperature magnetic susceptibility studies help characterize these complexees. X-ray studies help characterize crystal structures of the sigma nature of the Cu(Dopn)-M interaction.

HL reacts with Mn(CH3CO2)4.4H2O and sodium perchlorate to produce a tetranuclear complex (Mn4L6)(ClO4)2. X-ray analysis shows the complex's chain-like structure with two phenolate bridges connecting each adjacent pair of Mn(II) ions. Magnetic susceptibility measurement reveals the ferromagnetic exchange. Magnetic moment at 300 K is 5. 80 mu(B), which increases to 7.30 mu(B) at 4 K.

The magnetic susceptibility, the IR and UV-vis spectra, and the ESR 13C hyperfine couplings for inert triphenylmethyl diradicals were described. The study of these diradicals involved the insertion of different spacer chains in their central position to vary the nature of the link between the two moieties. These diradicals became chemically inert and stable when perchlorinated.

The dicarboxy (4,4'-dicarboxytridecachlorotriphenyl)methyl radical and its diester (4, 4-'Bis(methoxycarbonyl)tridecachlorotriphenyl)methyl radical are synthesized. ESR spectra show a single line and three factors identical for both the compounds. The molar magnetic susceptibility of the carboxyl radical is measured in the interval of 20-300K. Two or three-dimensional network with ferromagnetic interactions are absent in these compounds.

Dinucleating ligands containing pyridine and phenol are prepared and thin complexes with Fe(II) are examined. These complexes model the active sites of purple acid phosphatase. Magnetic susceptibilities of these compounds are also examined.

(Fe(OEP)(H2O))ClO4 or ((FE(OEP))2(OH))ClO4, instead of the anticipated perchlorato or bis(aquo) species, result from acid treatment of the mu-oxo bridge in (mu-oxo)(octaethyporphinato)iron(III). Aquo(octaethylporphinato)iron(III) perchlorate was subjected to X-ray structure identification, Mossbauer and magnetic susceptibility estimations and synthetic methodologies.

Preparation of a new member of the series M(n-x)Mo(4n+2)O(6n+4), Ba3Mo18O28 has been achieved at 1230 degrees C. A transport reaction using BaMoO4, MoO2 and Mo reagents in the presence of water vapor provides single crystals. Measurements of magnetic susceptibility and electrical sensitivity and single-crystal and powder X-ray diffraction characterize the complex.

The (dafoneH2)(CuCl3H2O)Cl crystal structure reveals the presence of an unusual coordinate water and semicoordinate Cl(minus)-containing chromophore (CUCl3H2O)Cl2- and moderately strong antiferromagnetic exchange pathway. The structure has Cl-Cl contact-linked planar chromophores and weak H-bonding. Single crystal EPR analysis confirms the presence of H binding-induced exchange between H2O and Cl.

Four synthesized ferromagnetic Ni(II) polynuclear complexes containing an end-on azido fragment as a bridging ligand form the first examples of one dimensional Ni(II)-azido ferromagnetic system. Two complexes crystallize in a monoclinic system whereas one crystallizes in a triclnic system. Measurement of susceptibility against temperature reveals that two of the four complexes are metamagnetic at lower temperature ranges.

A cylindrical specimen of ceramic superconducting YBa2Cu3O(7 - delta) is investigated in the frequency range from 0.5 to 1000 hertz to determine its imaginary and real parts of the susceptibility to alternating current volume. Between 2 and 250 hertz, the shielding diamagnetism depends on the frequency to a small extent. The peak loss temperature due to frequency variation is influenced by the logarithmic dependency, which indicates the current susceptibility is an activation process.

The process of hydrothermal preparation is employed in the synthesis of a novel vanadium phosphate with varying valences. Solitary crystal X-ray diffraction and magnetic susceptibility calculations are used to determine its properties. The geometry is seen as being elongated and derived from a VOPO4-like layer with the P-OH group, and V3+ octahedra accepted the ends of the elongated structure. Two varying areas for the K+ cations are yielded due to the piling of the layers, and are observed inside the layers and between two layers.

A three-dimensional ordering in MnCu(opba)(DMSO)3, MnCu(opba).0.7DMSO and (nBu4)2Mn2(Cu(opba))3 is controlled by the exchange interaction and not by the dipolar effect. The compounds were synthesized with opba or O-phenylenebis(oxamato). The structures of the complexes have distinct MnII-CuII zigzag chains. The copper atom is in square pyramidal environment, and the manganese atom is in an octahedral environment having a cis coordination.

Bulky clusters containing eight high-spin iron(III) ions of the formula (((tacn)6Fe8(mu3-O)2(mu2-OH)12)Br7-(H2O))Br.H2O, Fe8, tacn = 1,4,7-triazacyclononane were used to determine the magnetic susceptibility of large clusters. Results showed that the S = 10 spin rate can be described in terms of a dominant spin configuration where the time spins for Fe5, Fe6, Fe7 and Fe8 are parallel to each other. The Fe8 ion cluster was found to possess the highest spin in the ground state.

A superconductor which contains mercury, barium, calcium, copper and oxygen can measure temperature above 130 Kelvin. The mercury-based copper oxide has a simple structure and a reversibility line higher than double-layered bismuth-based or thallium-based conductors.

The complex (2,7,12,17-tetramethyl-3,8,13,18- tetramesithylporphyrinato)copper(II), Cu(TMTMP), was synthesized and substituted in the pyrrole beta-position to produce the a1u radical species and study the intramolecular magnetic interaction between the copper(II) and the a1u porphyrin radical spins. The oxidation of Cu(TMTMP) with Phenox-SbCl6 produced (Cu(TMTMP.))(SbCl6) which was characterized by electronic, NMR and ESR spectra.

The addition of copper nitrate trihydrate to a methanol/water solution of 1, 3-dimethyl-5-(2-carboxyphenyl azo)barbituric acid (LH2) at room temperature produces (CuL H2O)n in 81% yield. Syn-anti carboxylate moieties sequentially connect the Cu(II) ions forming innumerable ferromagnetic chains which stretch along the crystallographic a axis. The EPR spectroscopic analysis shows that the X-band spectrum of the compound is consistent with d(x2-y2) ground state Cu(II) ions.

Structural analysis, magnetic susceptibility measurements and ESR spectroscopic properties were studied for the dinuclear complexes ((TmenCu)2Tae(Clo4)2.H2O) (Tmen = N,N,N',N'-tetramethylenediamine; Tae = dianion of tetraacetylethane) and (TmenCu)2Tae.H2O(BPh4)2; and the mononuclear complex (TmenCuAcac(ClO4)) (Acac = acetylacetonato). Antiferromagnetic interactions, intermolecular or intramolecular, were observed for the three complexes.