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Two new NaI/CuI,II polynuclear compounds [(NaCu3((R,R)‐3‐MeOSalcy)2(NCO)2](1) and [(NaCu2(3‐MeOSalpn)(NCO)2] (2) have been synthesized using the Schiff base (SB) ligands, (R,R)‐3‐MeOSalcy=(R,R)–N,N′‐bis(3‐methoxysalicylidene)‐1,2‐diaminocyclohexane and 3‐MeOSalpn=N,N′‐bis(3‐methoxysalicylidene)‐1,3‐diaminopropane, respectively. Both complexes contain the rarely observed linear [Cu(NCO)2]− ion which links [{CuII(SB)}2Na]+ ions in 1 or [{CuII(SB)Na}2]2+ ions in 2 producing different linear chain topologies. The mixed valent CuI/IINa network in compound 1 allows for greater magnetic isolation of the paramagnetic ions as compared to compound 2, leading to differences in their EPR spectra. [ABSTRACT FROM AUTHOR]

A series of thirty six complexes obtained from acetonitrile solutions of Cu(NO3)2, Ln(NO3)3 and 2,2‐biyridine or 5,5‐dimethyl‐2,2‐bipyridine (Ln=La‐Yb excluding Pm) have been characterized. The crystals may be grouped into six types: Type‐I, [Cu(bpy)3][La(NO3)5(OH2)]; Type‐II, [Cu(bpy)3][Ln(NO3)5(OH2)] ⋅ 2CH3CN (Ln=Ce, Pr); Type‐IIa, [Cu(5,5‐dmbpy)3][Ln(NO3)5(OH2)] ⋅ 2CH3CN (Ln=La, Ce); Type‐III, [Cu(bpy)3][Ln(NO3)5] (Ln=Nd, Sm–Lu); Type‐IIIa [Cu(5,5‐dmbpy)3][Ln(NO3)5] (Ln=Pr, Nd, Sm‐Lu); Type‐IV, [Cu(5,5‐dmbpy)2(NO3)]2[Ln(NO3)5(OH2)]⋅CH3CN [Ln=La‐Nd, Sm‐Tb). The coordination numbers of the nitrato and aquonitrato lanthanide anions are 10 and 11, respectively. The tris‐chelates in Types I, II and IIIa undergo static Jahn‐Teller distortion while Types IIa and III support fluxional tris‐chelate ions. Type‐IV contains distortion isomers of [Cu(5,5‐dmbpy)2NO3]+. The structural trends are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. EPR and electronic spectral characteristics are discussed for the six types of compounds. [ABSTRACT FROM AUTHOR]

Five new polybromide compounds containing tris-chelates of 1,10-phenanthroline and 2, 2-bipyridine as counter cations are described: [Mn(phen)3](Br3)2 (1), [Co(phen)3](Br3)3 (3) and [M- (phen)3](Br3)(Br8)1 =2 where, M=Fe (2), Cu(4) or Zn(5). All are obtained by self assembly in solution starting from divalent transition metal bromides and bromine along with the ligand. In the case of CoBr2, bromine acts as a tribromide precursor as well as oxidising agent. The Mn compound is isomorphous with the corresponding triodide and analogously contains one short and one normal trihalide ion. The Co compound contains one bent but symmetric Br3 ion. The three compounds containing the Z-shaped octabromide ion are isostructural. While the cation in 1 has a crystallographically imposed C3 symmetry, the tris chelates in the other four compounds have near trigonal symmetry. Unusually, the trigonally compressed octahedral cation in 4 has six almost equal Cu N bond distances. Attempts to prepare bpy analogs of 1 resulted in a new dibromo-bridged compound [Mn2Br2(bpy)4](Br3)2 (6) and a dioxo-bridged compound [Mn2O2(bpy)4](Br3)3 (7). The mixed valence cation in 7 formed by bromine oxidation of MnBr2, followed by disproportionation, is well known with other anions. All the paramagnetic compounds (1, 4, 6, 7) give resolved EPR spectra since the bulky anions help to magnetically isolate the cations. The unsymmetric dibromo bridges in 6 produce a net, albeit weak, ferromagnetic coupling between the two [Mn(bpy)2] ²+ fragments. Raman as well as electronic spectra are reported for all compounds. Raman bands, though significantly different even for isostructural compounds, may be understood in terms of Br3 ions and Br2 molecules. All compounds give luminescence from phen and bpy both in solid and solution states, modulated by the coordinated metal io [ABSTRACT FROM AUTHOR]

This study proposes a comprehensive power management scheme (CPMS) for the economical and smart operation of a photovoltaic (PV) battery based Hybrid Microgrid (HMG) system. The solar-PV, DC-loads and battery storage are interfaced to DC-bus of the HMG. The battery is integrated into the DC-bus using a bidirectional energy storage converter (BESC). The voltage and frequency of AC-bus are regulated by utility grid and bidirectional interlinking converter (BIC) during grid-connected and islanded modes of operation, respectively. The proposed CPMS obviates high-speed communication link between converters for maintaining the system stability during power disturbances. Therefore, the vulnerability to collapse due to communication link failure is eliminated, thereby enhancing system reliability. The operational performance of HMG is improved with the proposed CPMS by providing additional features (minimisation of operating cost of the HMG, enhancement in voltage regulation of the DC-bus etc.) using low-speed communication network. The proposed CPMS can also be extended to a larger HMG system by utilising the full bandwidth of the communication network. Further, the proposed CPMS enables HMG to seamlessly switch from grid-connected to islanded mode and vice-versa. Experimental results validating the efficacy of the proposed CPMS are presented. [ABSTRACT FROM AUTHOR]

A series of thirteen complexes which may be formally considered as assembled from Cu(bpy)2(NO3)2 and Ln(NO3)3 (Ln=La−Yb excluding Pm, bpy=2,2'‐bipyridine) have been characterized. The crystals may be grouped into four classes: A, [Cu2(bpy)4(μ‐NO3)][Ln(NO3)6] (Ln=La−Nd); B, [Cu(bpy)2(NO3)]2[Ln(NO3)4(OH2)2](NO3) (Ln=Sm−Dy); C, [Cu(bpy)2(NO3)]2[Ln(NO3)5] (Ln=Ho−Tm); D, [Cu(bpy)2(NO3)]2 [Ln(NO3)3(OH2)3](NO3)2⋅2H2O (Ln=Yb). The coordination numbers of the nitrato or aquonitrato lanthanide anions range from 9 to 12. The dinuclear cation in Class A having a linear monoatomic nitrate bridge is new and is seen to produce weak antiferromagnetic coupling in these compounds. The other classes contain distortion isomers of [Cu(bpy)2NO3]+. The structural trends are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. EPR and electronic spectral characteristics are discussed for the four classes of compounds. Self assembly from acetonitrile solutions containing 2,2‐bipyridine and hydrates of Cu(NO3)2 and Ln(NO3)3 results in 13 CuII‐LnIII compounds belonging to four classes. The structural trends including the formation of the new dinuclear Cu(II) complex having linear monoatomic nitrato bridge as well as the unusual cocrystal of neutral lanthanide aquanitrate with Cu(II) complex salt are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. Magnetic properties, EPR and electronic spectral characteristics are also discussed. [ABSTRACT FROM AUTHOR]

Two new triply bridged Cu(II) compounds [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) (where, bpy=2,2'‐bipyridine) have been synthesized and their magnetic properties have been measured and correlated with structure. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges. The terminal Cu2+ ions have [5 + 1] coordination while the central ion has [4 + 2] coordination. The three centres are antiferromagnetically coupled, the exchange parameters for the neighbouring and distant pairs of Cu(II) atoms being 2 J=–28.6 cm–1 and 2 J'=–1.0 cm–1, respectively. In compound 2 three types bridging modes are observed, viz., hydroxo, aquo and carboxylato. The two Cu(II) centers are ferromagnetically coupled (2 J=73.8 cm–1) as previously observed for several di‐copper complexes with the same bridges. DFT calculations are in reasonable agreement with the magnetic exchange parameters for both dinuclear and trinuclear compounds. [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) are two new triply bridged Cu(II) compounds. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges and is antiferromagnetic while 2 is ferromagnetic. Their magnetic properties are correlated with structure and modeled well using DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: Five new chiral MnIII complexes [Mn((1R, 2R)‐Salcy)N3]∞⋅CH3CN (1), [Mn((R,R)‐Salcy)N3]∞ (2), [Mn((R,R)‐Salcy)N3] (4), [Mn((R,R)‐Salcy)(H2O)N3]⋅C4H8O (5) and [Mn((R,R)‐Salcy)NCS] (6) have been synthesized and characterized by X‐ray structural analysis and magnetic measurements (Salcy=N,N′‐bis(salicylidene)‐1,2‐diaminocyclohexane}. The four azido complexes have been obtained from the previously known [Mn((R,R)‐Salcy)(CH3OH)N3] (3) by crystallization from various solvents. Compounds 1 and 2 are trans‐μ‐1,3‐azide bridged coordination polymers. While 1 forms helical chains, the chain in 2 is formed via translation of a dimeric helicate repeat unit. Compound 3 is a methanol coordinated mononuclear azido complex which forms a 2D‐network through H‐bonding. Compounds 4 and 6 are phenoxo‐bridged dimers without inversion center. Compound 5 is an aqua coordinated mononuclear azido complex, which forms a 1D‐chain through O−H⋅⋅⋅N hydrogen bonding involving axial ligands. In all six compounds MnIII exhibits a characteristic Jahn−Teller elongation. The magnetic coupling in 1 and 2 leads to antiferromagnetic interaction along the chain (2 J=−11.6 cm−1 for 1 and –11.9 cm−1 for 2) through the μ‐1,3‐azide bridge. Compound 3 is weakly antiferromagnetic due to hydrogen bonding interactions in the lattice. The phenoxo dimers (4 and 6) do not have measurable exchange interaction, the low temperature susceptibility being influenced mainly by zero‐field splitting. [ABSTRACT FROM AUTHOR]

The reaction of CuII halides with 4,5-diazaflouren-9-one (dafone) in acetonitrile and in the presence of halogens gave four novel compounds: [Cu(dafone)2Cl2]Br2 (1), [Cu(dafone)2Br2]Br2 (2), [Cu(dafone)2(CH3CN)2](IBr2)2 (3), and [Cu(dafone)2(CH3CN)2](Br3)2(Br2)2 (4). The well-known preference of dafone to form an unsymmetrical chelate with Cu2+ directs the halide ion and acetonitrile to the equatorial plane of the octahedral complex. In 1 and 2, dibromine links the neutral halo complex molecules to form infinite chains of the previously known neutral molecules. The acetonitrile complex in 3 has the symmetrical mixed trihalide (IBr2–) as a counterion, while in 4 the cation is surrounded by a tribromide-dibromine network. Raman, EPR, optical absorption, and luminescence characteristics are discussed. The dibromine molecules in 1 and 2 provide a pathway for weak magnetic coupling along the chain polymer. [ABSTRACT FROM AUTHOR]

Two new iodobromides [I2Br62- (analogue of I82- and Br82-) and IBr4- (analogue of Br5- and I2Br3-)] and new chains formed from Br3-, Br2 and IBr4- have been obtained in three compounds all containing the same CuII tris-chelate cation Cu(dafone)32+ {[Cu(dafone)3](Br3)(Br5) ( 1), [Cu(dafone)3](Br5)(Br8)0.5·CH3CN ( 2) and [Cu(dafone)3](IBr4)(I2Br6)0.5·CH3CN ( 3)} by a procedure employing bromine, iodine, CuII bromide and dafone in acetonitrile. The formation of chains and isolated polyhalide ions is facilitated by templating with the tris-chelate cation. The Raman spectra of the polyhalides and EPR and other spectral characteristics of the fluxional CuII complex cation are presented. [ABSTRACT FROM AUTHOR]

Two new triply bridged Cu(II) compounds [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) (where, bpy=2,2'‐bipyridine) have been synthesized and their magnetic properties have been measured and correlated with structure. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges. The terminal Cu2+ ions have [5 + 1] coordination while the central ion has [4 + 2] coordination. The three centres are antiferromagnetically coupled, the exchange parameters for the neighbouring and distant pairs of Cu(II) atoms being 2 J=–28.6 cm–1 and 2 J'=–1.0 cm–1, respectively. In compound 2 three types bridging modes are observed, viz., hydroxo, aquo and carboxylato. The two Cu(II) centers are ferromagnetically coupled (2 J=73.8 cm–1) as previously observed for several di‐copper complexes with the same bridges. DFT calculations are in reasonable agreement with the magnetic exchange parameters for both dinuclear and trinuclear compounds. [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) are two new triply bridged Cu(II) compounds. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges and is antiferromagnetic while 2 is ferromagnetic. Their magnetic properties are correlated with structure and modeled well using DFT calculations. [ABSTRACT FROM AUTHOR]

The reaction of CuII halides with 4,5-diazaflouren-9-one (dafone) in acetonitrile and in the presence of halogens gave four novel compounds: [Cu(dafone)2Cl2]Br2 (1), [Cu(dafone)2Br2]Br2 (2), [Cu(dafone)2(CH3CN)2](IBr2)2 (3), and [Cu(dafone)2(CH3CN)2](Br3)2(Br2)2 (4). The well-known preference of dafone to form an unsymmetrical chelate with Cu2+ directs the halide ion and acetonitrile to the equatorial plane of the octahedral complex. In 1 and 2, dibromine links the neutral halo complex molecules to form infinite chains of the previously known neutral molecules. The acetonitrile complex in 3 has the symmetrical mixed trihalide (IBr2–) as a counterion, while in 4 the cation is surrounded by a tribromide-dibromine network. Raman, EPR, optical absorption, and luminescence characteristics are discussed. The dibromine molecules in 1 and 2 provide a pathway for weak magnetic coupling along the chain polymer. [ABSTRACT FROM AUTHOR]