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The trinuclear high-spin iron(III) complex [Fe3Cl3(saltagBr)(py)6]ClO4 {H5saltagBr = 1,2,3-tris[(5-bromo-salicylidene)amino]guanidine} was synthesized and characterized by several experimental and theoretical methods. The iron(III) complex exhibits molecular 3-fold symmetry imposed by the rigid ligand backbone and crystallizes in trigonal space group P3̅ with the complex cation lying on a crystallographic C3 axis. The high-spin states (S = 5/2) of the individual iron(III) ions were determined by Mösbauer spectroscopy and confirmed by CASSCF/CASPT2 ab initio calculations. Magnetic measurements show an antiferromagnetic exchange between the iron(III) ions leading to a geometrically spin-frustrated ground state. This was complemented by high-field magnetization experiments up to 60 T, which confirm the isotropic nature of the magnetic exchange and negligible single-ion anisotropy for the iron(III) ions. Muon-spin relaxation experiments were performed and further prove the isotropic nature of the coupled spin ground state and the presence of isolated paramagnetic molecular systems with negligible intermolecular interactions down to 20 mK. Broken-symmetry density functional theory calculations are consistent with the antiferromagnetic exchange between the iron(III) ions within the presented trinuclear high-spin iron(III) complex. Ab initio calculations further support the absence of appreciable magnetic anisotropy (D = 0.086, and E = 0.010 cm−1) and the absence of significant contributions from antisymmetric exchange, as the two Kramers doublets are virtually degenerate (ΔE = 0.005 cm−1). Therefore, this trinuclear high-spin iron(III) complex should be an ideal candidate for further investigations of spin-electric effects arising exclusively from the spin chirality of a geometrically frustrated S = 1/2 spin ground state of the molecular system.

The methanol solvomorph 1 amp; 8201; amp; 8901; amp; 8201;2MeOH of the cobalt II complex [Co LSal,2 amp; 8722;Ph 2] 1 with the sterically demanding Schiff base ligand 2 [1,1 amp; 8242; biphenyl] 2 ylimino methyl phenol HLSal,2 amp; 8722;Ph shows the thus far largest dihedral twist distortion between the two chelate planes compared to an ideal pseudotetrahedral arrangement. The cobalt II ion in 1 amp; 8201; amp; 8901; amp; 8201;2MeOH exhibits an easy axis anisotropy leading to a spin reversal barrier of 55.3 amp; 8197;cm amp; 8722;1, which corresponds to an increase of about 17 amp; 8201; induced by the larger dihedral twist compared to the solvent free complex 1. The magnetic relaxation for 1 amp; 8201; amp; 8901; amp; 8201;2MeOH is significantly slower compared to 1. An in depth frequency domain Fourier transform FD FT THz EPR study not only allowed the direct measurement of the magnetic transition between the two lowest Kramers doublets for the cobalt II complexes, but also revealed the presence of spin phonon coupling. Interestingly, a similar dihedral twist correlation is also observed for a second pair of cobalt II based solvomorphs, which could be benchmarked by FD FT THz EPR

The half-sandwich complex [Cp'Fe{N(dipp)(SiMe

The reaction of Co(NCS)

A cobalt(II)‐based spin triangle shows a significant spin–electric coupling. [Co3(pytag)(py)6Cl3]ClO4⋅3 py crystallizes in the acentric monoclinic space group P21. The intra‐triangle antiferromagnetic interaction, of the order of ca. −15 cm−1 (H=−JSaSb), leads to spin frustration. The two expected energy‐degenerate ground doublets are, however, separated by a few wavenumbers, as a consequence of magnetic anisotropy and deviations from threefold symmetry. The Co3 planes of symmetry‐related molecules are almost parallel, allowing for the determination of the spin–electric properties of single crystals by EFM‐ESR spectroscopy. The spin–electric effect detected when the electric field is applied in the Co3 plane was revealed by a shift in the resonance field. It was quantified as ΔgE/E=0.11×10−9 m V−1, which in terms of frequency corresponds to approximately 0.3 Hz m V−1. This value is comparable to what was determined for a Cu3 triangle despite the antiferromagnetic interaction being 20 times larger for the latter., This contribution describes the observation of spin–electric coupling utilizing electric‐field‐modulated ESR (EFM‐ESR) spectroscopy for single‐crystals of a spin triangle which is characterized by the strong magnetic anisotropy of the individual cobalt(II) centers and a pronounced sensitivity of the molecular energy levels on the relative orientation of their magnetic axes as well as the exchange coupling between them.

A large single crystal of a compound from the family of coordination polymer [Co(NCS)2(L)2]n chains was synthesized and its magnetic properties are reported. [Co(NCS)2(4-(3-phenylpropyl)pyridine)2]n is ferromagnetic with Tc = 3.39 K. Single-ion ab initio calculations predict an almost Ising-type magnetic anisotropy and the direction of the magnetic easy-axis nearly along the Co–Npy bond of the apical pyridine-based co-ligand. Both predictions are confirmed by single-crystal magnetic measurements. The magnetic relaxation of the single crystal sample significantly differs from the powder sample data, and clearly shows the presence of two separate relaxation processes. The process dominant below 3.2 K demonstrates a single chain magnet (SCM) behaviour, with a crossover between single-wall and two-wall processes, in spite of the fact that the system is ferromagnetically ordered. The faster process that dominates just below Tc is attributed to spin waves. Micromagnetic Monte Carlo simulations of the investigated compound show that the dipolar field cancels for some chains located at the border between 3-dimensional domains. Such chains are responsible for the measured ac signal, and demonstrate the SCM behaviour. The quantitative analysis of the SCM relaxation time is supported by preparing and examining a corresponding diamagnetically diluted compound, [CoxCd1−x(NCS)2(4-(3-phenylpropyl)pyridine)2]n (x = 0.013), which behaves as a field-induced single-ion magnet. The relaxation pathways for single Co(II) spins are determined to be Raman, direct, and quantum tunneling processes, which were included in an improved approach to describe the magnetic relaxation in the Co(II)-based SCM compound.

No previous study assessed the combined effect of olive pruning residues (OLPR) and spent coffee grounds (SCG) on P. ostreatus production and nutritional value. The aim of this study was to determine the capacity of P. ostreatus to degrade lignocellulosic nature of combined OLPR and SCG as well as their resultant nutrient composition. A complete randomized design was adopted with five treatments: S1:100%wheat straw (WS) (control), S2:33%WS+33%SCG+33%OLPR,S3:66%WS+17%SCG+17%OLPR,S4:17%WS+66%SCG+17%OLPR, and S5:17%WS+17%SCG+66%OLPR, and ten replicates per treatment. Substrate’s and mushroom’s composition were analyzed on chemical scale, including fatty acids and heavy metals profiles, following international standards. Only S1, S2, and S3 were productive, with comparable biological yield, economical yield, and biological efficiency. Organic matter loss decreased with increasing proportions of OLPR and SCG. Percentage lignin loss was higher in S1 than in S2 and S3 (53.51, 26.25, and 46.15% respectively). Mushrooms of S3 had some enhanced nutritional attributes compared to control: decrease in fat, increase in protein, increase in monounsaturated fatty acids, and lower zinc accumulation. Lead was less accumulated in S2 than S1 mushrooms. Sodium content of mushroom decreased in S2 and S3. The latter substrates yielded mushrooms with lower polyunsaturated fatty acids (PUFA) and higher saturated fatty acids (SFA) contents. All mushrooms had a valuable PUFA/SFA. This study suggests using OLPR and SCG in low proportions as nutritional supplements to the commercial wheat straw.

Three new nickel phosphonate complexes {[Na2Ni8(L)6]·nSolv}m (L = SAA3− (1), BSAA3− (2), NAA3− (3); Solv = H2O, MeOH; m = ∞ (1, 2), 1 (3)) were synthesized. All three complexes possess a novel octanuclear {Ni8} phosphonate core, which consists of four dinuclear doubly oxygen-bridged units, further interconnected to each other by phosphonate oxygen bridges. The steric features of the ligands influence the aggregation degree. Molecules of 1 and 2 are interconnected by sodium cations into 2D layered and 1D chain extended structures, respectively, while the molecules of 3 with the bulkiest ligand are not bonded with each other. Magnetic properties of the obtained {Ni8} core unit were studied for complex 1 as a representative of this family of compounds and are reported in detail. Magnetic susceptibility at low temperature is indicative of a singlet ground state. The absence of saturation and the magnetization behavior points to zero-field splitting (ZFS). Simulation of the magnetization data revealed an easy-plane magnetic anisotropy with an axial ZFS parameter D = 7.4 cm−1. The magnetic properties of 1 were also studied by broken-symmetry DFT calculations (BS-DFT), which revealed the presence of ferromagnetic exchange interactions within the dinuclear units of the {Ni8} core with a dominant antiferromagnetic interaction between these dinuclear entities. These results are in good agreement with coupling constants derived from the experimental susceptibility and magnetization data.

A large single crystal of a compound from the family of coordination polymer [Co(NCS)2(L)2]n chains was synthesized and its magnetic properties are reported. [Co(NCS)2(4-(3-phenylpropyl)pyridine)2]n is ferromagnetic with Tc = 3.39 K. Single-ion ab initio calculations predict an almost Ising-type magnetic anisotropy and the direction of the magnetic easy-axis nearly along the Co-Npy bond of the apical pyridine-based co-ligand. Both predictions are confirmed by single-crystal magnetic measurements. The magnetic relaxation of the single crystal sample significantly differs from the powder sample data, and clearly shows the presence of two separate relaxation processes. The process dominant below 3.2 K demonstrates a single chain magnet (SCM) behaviour, with a crossover between single-wall and two-wall processes, in spite of the fact that the system is ferromagnetically ordered. The faster process that dominates just below Tc is attributed to spin waves. Micromagnetic Monte Carlo simulations of the investigated compound show that the dipolar field cancels for some chains located at the border between 3-dimensional domains. Such chains are responsible for the measured ac signal, and demonstrate the SCM behaviour. The quantitative analysis of the SCM relaxation time is supported by preparing and examining a corresponding diamagnetically diluted compound, [CoxCd1-x(NCS)2(4-(3-phenylpropyl)pyridine)2]n (x = 0.013), which behaves as a field-induced single-ion magnet. The relaxation pathways for single Co(ii) spins are determined to be Raman, direct, and quantum tunneling processes, which were included in an improved approach to describe the magnetic relaxation in the Co(ii)-based SCM compound.

Reaction of Co(NCS)2 with 4-bromopyridine leads to the formation of discrete complexes with the composition Co(NCS)2(4-bromopyridine)4·(CH3CN)0.67 (1), Co(NCS)2(4-bromopyridine)2(H2O)2 (2), Co(NCS)2(4-bromopyridine)2(CH3OH)2 (3) and Co(NCS)2(4-bromopyridine)2(CH3CN)2 (4). Upon heating compounds 2 and 4 transform into a crystalline product with the composition Co(NCS)2(4-bromopyridine)2 (5-I) that also can easily be obtained from solution. In this compound, the Co cations are linked by single μ-1,3-bridging thiocyanate anions into layers. Thermal decomposition of 3 leads to a second isomer (5-II), which is thermodynamically metastable and can also be synthesized from solution under kinetic control. In contrast to 5-I, the Co cations are linked by pairs of anionic ligands into linear chains. The magnetic exchange is very weak in 5-I, but much stronger and ferromagnetic along the linear chains in 5-II. AF ordering in 5-II is reached at 3.05 K, and magnetic relaxation is observed at the metamagnetic transition with an Arrhenius barrier of 17.1(3) cm-1. Ab initio computational studies reveal a different type of magnetic anisotropy to be present in the two crystallographically - independent Co centers in 5-II.

Magnetic properties of coordination polymers like single-chain magnets (SCMs) are based on magnetic domains, which are formed due to magnetic exchange between neighboring anisotropic spin centers. However, the computational restrictions imposed by the high level of theory needed for an adequate ab initio quantum mechanical treatment on the basis of multi-reference methods for these systems limit the feasibility of such calculations to mononuclear fragments as appropriate structural cutouts for the metal centers along the chains. Hence, results from such calculations describe single-ion properties and cannot be directly correlated with experimental data representing magnetic domains. We present a theoretical approach based on n-membered Ising-spin rings with n = 3-12, which allows us to simulate magnetic domains and to derive important magnetic properties for SCM compounds. Magnetic exchange, which is not provided by calculations of mononuclear fragments, is obtained by fitting the theoretical magnetic susceptibility against experimental data. The presented approach is tested for cobalt(ii)-based SCMs with three types of repeating sequences, which differ in nuclearity and symmetry. The magnetic parameters derived using the presented approach were found to be in good agreement with the experimental data. Moreover, the energy spectra obtained for the three test cases using the presented approach are characteristic of a deviation of the individual systems from the ideal Ising behavior. An extrapolation technique towards larger systems (n > 12) is presented which can provide information on the statistical mean length of the magnetic domains in the three investigated SCM compounds.

Two different isomers of [Co(NCS)

Dysprosium(III) ions are promising candidates for the design of single-ion magnets (SIMs) as they show an intrinsic strong magnetic anisotropy. However, time-demanding multireference methods are usually necessary to reproduce low-lying magnetic states. In this work, we present an improved wave function-based semiempirical ligand-field (LF) theory approach to obtain magnetochemical properties of dysprosium(III)-based SIMs. We reduce the computational effort by replacing the central dysprosium(III) ion with either yttrium(III) or lutetium(III), which allows to obtain a closed-shell wave function from Hartree-Fock calculations. The wave function is subsequently used to determine a so-called diamagnetic-electrostatic pseudo-potential (DEPP) of the compound, which in turn can be applied to LF theory to obtain magnetochemical properties. The presented approach is tested against ab initio CASSCF/RASSI-SO reference calculations and shows accurate prediction of magnetic anisotropy axes and a significant accuracy improvement as compared to point charge-based LFT methods. In addition, we also introduce an improved electrostatic (IES) approach, which applies the obtained DEPPs to a known electrostatic method introduced by Chilton et al. (Nat. Commun. 2013, 4, 2551) to obtain the direction of the main anisotropy axis in dysprosium(III)-based SIMs. © 2018 Wiley Periodicals, Inc.

Zusammenfassung Die Kommunalen Gesundheitskonferenzen (KGKen) übernehmen in Baden-Württemberg eine zentrale Funktion in der Weiterentwicklung des Gesundheitswesens. Sie arbeiten auf Grundlage des Landesgesundheitsgesetzes auf Land- und Stadtkreisebene. Erste KGKen wurden hierzulande im Jahr 2010 eingerichtet. Bereits acht Jahre später weisen die KGKen eine große Bandbreite an Aktivitäten auf.

The synthesis of ethoxido-bridged dinuclear oxidovanadium(IV) complexes of the general formula (HNEt3)[(VOL1-3)2(μ-OEt)] (1-3) with the azo dyes 2-(2'-carboxy-5'-X-phenylazo)-4-methylphenol (H2L1, X = H; H2L2, X = NO2) and 2-(2'-carboxy-5'-Br-phenylazo)-2-naphthol (H2L3) as ligands is reported. The ligands differ in the substituents at the phenyl ring to probe their influence on the redox behavior, biological activity, and magnetochemistry of the complexes, for which the results are presented and discussed. All synthesized ligands and vanadium(IV) complexes have been characterized by various physicochemical techniques, namely, elemental analysis, electrospray ionization mass spectrometry, spectroscopic methods (UV/vis and IR), and cyclic voltammetry. X-ray crystallography of 1 and 3 revealed the presence of a twisted arrangement of the edged-shared bridging core unit. In agreement with the distorted nature of the twisted core, antiferromagnetic exchange interactions were observed between the vanadium(IV) centers of the dinuclear complexes with a superexchange mechanism operative. These results have been verified by DFT calculations. The complexes were also screened for their in vitro cytotoxicity against HeLa and HT-29 cancer cell lines. The results indicated that all the synthesized vanadium(IV) complexes (1-3) were cytotoxic in nature and were specific to a particular cell type. Complex 1 was found to be the most potent against HeLa cells (IC50 value 1.92 μM).

Cobalt(ii) complexes with different dihedral angles between the bidentate ligands show a significant variation in their magnetic relaxation behavior.

Five new lanthanide(III) sandwich and half-sandwich complexes with bulky cyclooctatetraenyl ligands have been prepared and fully characterized, including single-crystal X-ray structure determination. Treatment of anhydrous lanthanide(III) chlorides, LnCl3 (Ln = Pr, Tb, Yb), with 2 equiv. of Li2COT'' (COT'' = 1,4-bis(trimethylsilyl)-cyclooctatetraene dianion) followed by crystallization in the presence of coordinating solvent afforded the anionic sandwich complexes [Li(THF)4][Pr(COT″)2] (1), [Li(DME)3][Tb(COT″)2] (2), and [Li(TMEDA)2][Yb(COT″)2] (3). Attempted oxidation of 2 with silver iodide did not afford the neutral terbium(IV) sandwich complex Tb(COT″)2. Instead, the tri(µ-iodido)-bridged dinuclear half-sandwich complex Li(DME)2Tb2(µ-I)3(COT'')2 was isolated in 72% yield. In this complex, a Li(DME)2 fragment is attached to one of the µ-iodido ligands. A closely related binuclear lutetium complex, [Li(DME)3][Lu2(µ-Cl)3(COTbig)2]∙DME (5), was obtained using the "superbulky" COTbig ligand (COTbig = 1,4-bis(triphenylsilyl)cyclooctatetraenyl dianion). In addition to the spectroscopic and structural characterization, the magnetic properties of the paramagnetic terbium(III) derivative 2 have been investigated and further complemented by ab initio computational methods. These results are used to discuss the structural requirement for potential terbium(III) single-ion magnets.

Reaction of Co(NCS)2 with different coligands leads to the formation of three compounds with the general composition [Co(NCS)2(L)2]n (L = aniline (1), morpholine (2), and ethylenethiourea (3)). In ...

Reaction of Co(NCS)2 with 4-bromopyridine leads to the formation of discrete complexes with the composition Co(NCS)2(4-bromopyridine)4·(CH3CN)0.67 (1), Co(NCS)2(4-bromopyridine)2(H2O)2 (2), Co(NCS)2(4-bromopyridine)2(CH3OH)2 (3) and Co(NCS)2(4-bromopyridine)2(CH3CN)2 (4). Upon heating compounds 2 and 4 transform into a crystalline product with the composition Co(NCS)2(4-bromopyridine)2 (5-I) that also can easily be obtained from solution. In this compound, the Co cations are linked by single μ-1,3-bridging thiocyanate anions into layers. Thermal decomposition of 3 leads to a second isomer (5-II), which is thermodynamically metastable and can also be synthesized from solution under kinetic control. In contrast to 5-I, the Co cations are linked by pairs of anionic ligands into linear chains. The magnetic exchange is very weak in 5-I, but much stronger and ferromagnetic along the linear chains in 5-II. AF ordering in 5-II is reached at 3.05 K, and magnetic relaxation is observed at the metamagnetic transition with an Arrhenius barrier of 17.1(3) cm-1. Ab initio computational studies reveal a different type of magnetic anisotropy to be present in the two crystallographically - independent Co centers in 5-II.

The cobalt(II) in [Co(NCS)2(4‐methoxypyridine)2]n are linked by pairs of thiocyanate anions into linear chains. In contrast to a previous structure determination, two crystallographically independent cobalt(II) centers have been found to be present. In the antiferromagnetic state, below the critical temperature (T c=3.94 K) and critical field (H c=290 Oe), slow relaxations of the ferromagnetic chains are observed. They originate mainly from defects in the magnetic structure, which has been elucidated by micromagnetic Monte Carlo simulations and ac measurements using pristine and defect samples. The energy barriers of the relaxations are Δτ1=44.9(5) K and Δτ2=26.0(7) K for long and short spin chains, respectively. The spin excitation energy, measured by using frequency‐domain EPR spectroscopy, is 19.1 cm−1 and shifts 0.1 cm−1 due to the magnetic ordering. Ab initio calculations revealed easy‐axis anisotropy for both CoII centers, and also an exchange anisotropy Jxx/Jzz of 0.21. The XXZ anisotropic Heisenberg model (solved by using the density renormalization matrix group technique) was used to reconcile the specific heat, susceptibility, and EPR data., Slowly relax… The magnetic properties of the linear chain compound [Co(NCS)2(4‐methoxypyridine)2]n have been investigated both experimentally and theoretically. Slow relaxations of the ferromagnetic chains were observed in the antiferromagnetic state and the specific heat, susceptibility, and EPR data obtained have been reconciled by using the XXZ anisotropic Heisenberg model (see figure).

Two different isomers of [Co(NCS)2(4-chloropyridine)2]n (3C and 3L) were synthesized from solution and by thermal decomposition of Co(NCS)2(4-chloropyridine)2(H2O)2 (2), which show a different meta...

Correction for 'Magnetic relaxation in cobalt(ii)-based single-ion magnets influenced by distortion of the pseudotetrahedral [N

Two new transition metal thiocyanate coordination polymers with the composition [Co(NCS)2(4-vinylpyridine)2]n (1) and [Co(NCS)2(4-benzoylpyridine)2]n (2) were synthesized and their crystal structures were determined. In both compounds the Co cations are octahedrally coordinated by two trans-coordinating 4-vinyl- or 4-benzoylpyridine co-ligands and four μ-1,3-bridging thiocyanato anions and linked into chains by the anionic ligands. While in 1 the N and the S atoms of the thiocyanate anions are also in trans-configuration, in 2 they are in cis-configuration. A detailed magnetic study showed that the intra-chain ferromagnetic coupling is slightly stronger for 2 than for 1, and that the chains in both compounds are weekly antiferromagnetically coupled. Both compounds show a long range magnetic ordering transition at Tc = 3.9 K for 1 and Tc = 3.7 K for 2, which is confirmed by specific heat measurements. They also show a metamagnetic transition at a critical field of 450 Oe (1) and 350 Oe (2), respectively. Below Tc1 and 2 exhibit magnetic relaxations resembling relaxations of single chains. The exchange constants obtained from magnetic and specific heat data are in good accordance with those obtained from constrained DFT calculations carried out on isolated model systems. The ab initio calculations allowed us to find the principal directions of anisotropy.

[Co(NCS)2(py)2]n (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. Magnetic and specific heat studies show that the compound undergoes a phase transition at 3.7 K to a ferromagnetic state. The determined magnetic interactions, intrachain (J/kB = 28 K) and interchain (zJ'/kB = 0.5 K), confirm the quasi 1D Ising magnetic character of [Co(NCS)2(py)2]n. Using AC magnetic susceptibility measurements the energy barriers for magnetization reversal of different relaxation processes were determined including those of the individual chains. By means of high field-high frequency ESR study the magnetic excitations were observed and explained in the frame of the Ising model in agreement with the results of the magnetic study. Ab initio calculations confirm the high magnetic anisotropy of the system and allow determination of the direction of the easy-axis. The broken symmetry DFT calculations support the ferromagnetic intrachain interactions. The energetic relations relevant for relaxations are discussed. It is concluded that the magnetic model of [Co(NCS)2(py)2]n is not a pure Ising but the transversal exchange plays a role.

Effects of two coloured plastic films (‘Half Minus Green 248’ and ‘Pale Lavender 136’) 1 with different values of photosynthetically active radiation (‘Half Minus Green 248’: 120 ± 49 μmol m −2 s −1 , ‘Pale Lavender 136’: 83 ± 38 μmol m −2 s −1 ) and light spectra on growth, fresh and dry matter, nutrient solution uptake and secondary metabolites of Perilla frutescens grown in greenhouse were compared to natural light (154 ± 57 μmol m −2 s −1 photosynthetically active radiation). Both films differed in transmission of blue, green and red light, where ‘Pale Lavender 136’ had much lower transmission (62.00% blue, 39.00% green, 71.00% red light) than ‘Half Minus Green 248’ (75.40% blue, 65.25% green, 88.00% red light). ‘Half Minus Green 248’ film had higher red: far-red (660 nm: 730 nm) ratio (0.98) than ‘Pale Lavender 136’ film (0.82), but lower blue: red (400–500 nm: 600–700 nm) ratio (0.83) than ‘Pale Lavender 136’ film (0.92). Fresh matter under the plastic films was not lower than in the control after 3 weeks of cultivation. Compared to control dry matter (15.51%), ‘Pale Lavender 136’ treatment showed no significant difference, while under ‘Half Minus Green 248’ film significantly lower dry matter (13.77%) was recorded. Use of ‘Half Minus Green 248’ film did not have significant influence on nutrient solution uptake, while ‘Pale Lavender 136’ film reduced it by 11.91% comparing to control. Plant height increased significantly by 18.60% under ‘Half Minus Green 248’ film and by 15.61% in ‘Pale Lavender 136’ treatment compared to control which average height was 34 cm. Regarding concentration of secondary metabolites, use of ‘Pale Lavender 136’ film reduced it but not significantly compared to control. Use of ‘Half Minus Green 248’ film resulted in significantly lower concentration of anthocyanins (−81.36%) and polyphenols (−55.74%), as well as in reduced antioxidant activities (−53.63%). The flavonoid concentration did not differ between the treatments. The plant yield and the concentration of secondary metabolites could not be affected positively by the use of these plastic films, but with ‘Pale Lavender 136’ the same yield could be obtained with less nutrient uptake.

Two novel dioxidomolybdenum(VI) complexes [MoO2L′1] (1) and [MoO2L′2] (2) containing the MoO22+ motif with unexpected coordination motifs due to ligand rearrangement through Mo-mediated interligand C–C bond formation are reported. The ligands (H2L′1–2) are tetradentate C–C-coupled O2N2-donor systems formed in situ during synthesis of the complexes by reaction of [MoVIO2(acac)2] with Schiff base ligands of 2-aminophenol with 2-pyridinecarbaldehyde (HL1) and 2-quinolinecarbaldehyde (HL2). To confirm that the ligand rearrangement is assisted by molybdenum, the corresponding vanadium complexes [VO2L1] (3) and [VO2L2] (4) containing original Schiff base ligand (HL1,2) are also reported here. All complexes 1–4 are characterized by several physicochemical techniques and the structural features of 1 and 2 have been solved by X-ray crystallography. The proposed mechanism of molybdenum-mediated interligand C–C bond formation is supported by DFT calculations including the comparisons with the synthesized vanadium analogues. The catalytic potentials of 1–4 for the epoxidation of styrene and cyclohexene have also been explored.

Mainly because of the large number of people affected and associated significant health policy implications, the Robert Koch Institute (RKI) is developing a public health surveillance system using diabetes as an example. In a first step to ensure long-term and comparable data collection and establish efficient surveillance structures, the RKI has defined a set of relevant indicators for diabetes surveillance. An extensive review of the available literature followed by a structured process of consensus provided the basis for a harmonised set of 30 core and 10 supplementary indicators. They correspond to the following four fields of activity: (1) reducing diabetes risk, (2) improving diabetes early detection and treatment, (3) reducing diabetes complications, (4) reducing the disease burden and overall costs of the disease. In future, in addition to the primary data provided by RKI health monitoring diabetes surveillance needs to also consider the results from secondary data sources. Currently, barriers to accessing this data remain, which will have to be overcome, and gaps in the data closed. The RKI intentends to continuously update this set of indicators and at some point apply it also to further chronic diseases with high public health relevance.

The new tritopic triaminoguanidine-based ligand 1,2,3-tris[(pyridine-2-ylmethylidene)amino]guanidine (H2pytag) was synthesized. The reaction of a mixture of cobalt(II) chloride and cobalt(II) perchlorate with the ligand H2pytag in pyridine solution leads to the formation of the trinuclear cobalt(II) complex [Co3(pytag)(py)6Cl3]ClO4. Three octahedrally coordinated high-spin cobalt(II) ions are linked through the bridging triaminoguanidine backbone of the ligand leading to an almost equilateral triangular arrangement. The magnetic properties of the complex were investigated by magnetic measurements, variable-temperature, variable-field magnetic circular dichroism (MCD) spectroscopy, and density functional theory as well as ab initio calculations. A rather strong antiferromagnetic exchange interaction between the cobalt(II) centers of ca. −12 cm–1 is determined together with a strong local anisotropy. The single-ion anisotropy of all three cobalt(II) centers is found to be easy-plane, which coincides with th...

[Co(NCS)

SUMMARYA monitoring study was carried out in Gumara watershed, upper Blue Nile basin, with the objective of evaluating livestock water productivity (LWP) using a life cycle assessment method. Sixty two smallholder farmers were selected for the study implemented between November 2006 and February 2008. Data on crop and livestock production were collected to allow assessment of livestock water productivity. Study sites were situated in three different rainfed mixed crop/livestock farming systems; barley/potato based system (BPS), tef/finger-millet based system (TMS), and rice/noug based system (RNS). LWP was found to be significantly lower (p < 0.01) in RNS (0.057 USD m−3 water) than in TMS (0.066 USD m−3 water) or in BPS (0.066 USD m−3 water). Notably, water requirement per kg live weight of cattle increased towards the lower altitude area (in RNS) mainly because of increased evapo-transpiration. As a result, 20% more water was required per kg live weight of cattle in the low ground RNS compared to BPS situated in the upstream parts of the study area. Cattle herd management that involved early offtake increased LWP by 28% over the practice of late offtake. Crop water productivity expressed in monetary units (0.39 USD m−3 water) was higher than LWP (0.063 USD m−3 water) across the mixed farming systems of Gumara watershed. Strategies for improving LWP, from its present low level, could include keeping only the more productive animals, increasing pasture productivity and linking production to marketing. These strategies would also ease the imbalance between the existing high livestock population and the declining carrying capacity of natural pasture.

The synthesis, structure, and magnetic properties of two mononuclear cobalt(ii) complexes [Co(LSal,2-Ph)2] (1) and [Co(LNph,2-Ph)2] (2) are reported. The utilized sterically demanding Schiff-base ligands HLSal,2-Ph (2-(([1,1'-biphenyl]-2-ylimino)methyl)phenol) and HLNph,2-Ph (1-(([1,1'-biphenyl]-2-ylimino)methyl)naphthalen-2-ol) lead to a strong distortion of the [N2O2] coordination environment in the complexes 1 and 2, which can be primarily attributed to the variation in the dihedral angle between the planes of the two chelate ligands. Magnetic susceptibility and FD-FT THz-EPR measurements as well as ab initio calculations reveal that both complexes exhibit an easy-axis type of anisotropy. For both compounds frequency-dependent ac susceptibility measurements show an out-of-phase susceptibility under applied static fields of 400 and 1000 Oe. A detailed analysis of the underlying relaxation process is given, revealing significant differences in the contributions of Orbach, Raman, and direct processes within the observed temperature range. Fitting of the magnetic data leads to a spin-reversal barrier of 49 cm-1 for 1 at an applied field of 1000 Oe. For 2 the barrier is not well defined by the analysis of the relaxation times and is, therefore, approximated by the experimental barrier derived from FD-FT THz-EPR measurements (62.8 cm-1). The results from ab initio calculations and FD-FT THz-EPR measurements show that the distortion of the coordination sphere in complexes 1 and 2 from the pseudotetrahedral towards a square-planar coordination geometry leads to an increase in both the axial (D) and the rhombic zero-field splitting (E).

Collective action, on communal grazing land, has evolved in the highlands of northwestern Ethiopia to mitigate the problems of feed shortage and land degradation due to overgrazing. The exercise is liked by farmers for improving the availability of natural pasture during the long dry season when other feed sources get depleted. However, large portions of the communal grazing lands are still managed under free grazing throughout the year. This study was undertaken in Maynet village in the upper Blue Nile basin, northwestern Ethiopia, to assess the impacts of three different types of grazing land management (GLM) and two slope gradients (

Two new transition metal thiocyanate coordination polymers with the composition [Co(NCS)

Reaction of cobalt(II) and nickel(II) thiocyanate with ethylisonicotinate leads to the formation of [M(NCS)2(ethylisonicotinate)2]n with M = Co (2-Co) and M = Ni (2-Ni), which can also be obtained by thermal decomposition of M(NCS)2(ethylisonicotinate)4 (M = Co (1-Co), Ni (1-Ni)). The crystal structure of 2-Ni was determined by single crystal X-ray diffraction. The Ni(II) cations are octahedrally coordinated by two N and two S bonding thiocyanate anions and two ethylisonicotinate ligands and are linked by pairs of anionic ligands into dimers, that are connected into layers by single thiocyanate bridges. The crystal structure of 2-Co was refined by Rietveld analysis and is isostructural to 2-Ni. For both compounds ferromagnetic ordering is observed at 8.7 K (2-Ni) and at 1.72 K (2-Co), which was also confirmed by specific heat measurements. Similar measurements on [Co(NCS)2(4-acetylpyridine)2]n that exhibits the same layer topology also prove magnetic ordering at 1.33 K. Constrained DFT calculations (CDFT) support the ferromagnetic interactions within the layers. The calculated exchange constants in 2-Ni were used to simulate the susceptibility by quantum Monte Carlo method. The single-ion magnetic anisotropy of the metal ions has been investigated by CASSCF/CASPT2 calculations indicating significant differences between 2-Ni and 2-Co.

The role of agricultural land use and its contribution to flood risks were the focus of the research project MinHorLam. Schematised models were applied to assess the impacts of different farming practices or of land use patterns on runoff formation as well as on water levels and flow velocities in flood conditions. The results show the range, potentials and limits of agricultural measures to mitigate flood risks. Aspects of matter accumulation in floodplains and management options were presented from case study results related to extreme flood events. Empirical social research on farmers' and administrators' perspectives complemented the analyses. Institutional actors from water management and agriculture rated agriculture as playing a moderate to low role in causing flood events. Also hazards caused by floods or heavy rain are usually of minor importance in farmers' managerial decisions if there is no immediate risk or damage. Nevertheless, to enhance risk prevention in agriculture, more action is needed, especially cooperation among different institutional actors in flood risk management and agriculture. Copyright © 2011 John Wiley & Sons, Ltd.

Four new triphenylamine ligands with different substituents in the para position and their corresponding copper(II) complexes are reported. This study includes their structural, spectroscopic, magnetic, and electrochemical properties. The complexes possess a dinuclear copper(II) paddle‐wheel core, a building unit that is also common in metal‐organic frameworks. Electrochemical measurements demonstrate that the triphenylamine ligands and the corresponding complexes are susceptible to oxidation, resulting in the formation of stable radical cations. The square‐wave voltammograms observed for the complexes are similar to those of the ligands, except for a slight shift in potential. Square‐wave voltammetry data show that, in the complexes, these oxidations can be described as individual one‐electron processes centered on the coordinated ligands. Spectroelectrochemistry reveals that, during the oxidation of the complexes, no difference can be detected for the spectra of successively oxidized species. For the absorption bands of the oxidized species of the ligands and complexes, only a slight shift is observed. ESR spectra for the chemically oxidized complexes indicate ligand‐centered radicals. The copper ions of the paddle‐wheel core are strongly antiferromagnetic coupled. DFT calculations for the fully oxidized complexes indicate a very weak ferromagnetic coupling between the copper ions and the ligand radicals, whereas a very weak antiferromagnetic coupling is found among the ligand radicals.

The Front Cover shows a scene illustrating the need to investigate the properties of building blocks for complex systems to enable the basic design of new functional materials. It shows a model of the investigated paddle‐wheel complexes with copper‐bonded triphenylamines. Both paddle‐wheel units and triarylamine linkers are basic constituents found in several frameworks such as the networks shown in the image. More information can be found in the Full Paper by O. Akintola et al. on page 266 in Issue 3, 2019 (DOI: 10.1002/open.201800243).