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Two isostructural mononuclear complexes of lanthanides (Ln = La and Pr) constructed from 1,8-naphthalene dicarboxylate (NDC) and 1,10-phenanthroline (Phen) as auxiliary ligand are reported. Both the complexes were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride with Phen ligands. 3D supramolecular structures are observed which are guided by different weak interactions. The crystal structures of both the complexes were determined by single crystal X-ray diffraction. The room temperature photoluminescence studies, carried out in the powder state displayed three noticeable peaks from excited (3PJ; J = 2, 1, and 0) to ground state (3H4) at ~464 nm, 497 nm, and 538 nm, respectively, under UV excitation. Temperature dependent dc susceptibility (χ = M/H) as a function of temperature is investigated where Pr-complex shows antiferromagnetic behaviour. The Hirshfeld surface analysis of the two complexes is also described. [ABSTRACT FROM AUTHOR]

Using a solvothermal method, we have synthesized two coordination polymers of Cu(II). One is a 1D polymer {[Cu(bpy)(NDC)(H2O)]·2H2O}n (1, 1D) formed with 1,8-naphthalene dicarboxylic acid (H2NDC) and 2,2′-bipyridine (bpy) as an auxiliary ligand, while the other is a 2D polymer {[Cu3(TMA) (Imd)3]·5H2O·2DMF}n (2, 2D) formed with trimellitic acid (H3TMA) and imidazole (Imd) as an auxiliary ligand. Both coordination polymers 1 and 2 were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride and trimelitic anhydride with bipyridine and imidazole ligands, respectively. The asymmetric unit of polymer 1 contains asymmetric η1 binding mode (one of the carboxylate) linking distorted square-pyramidal [Cu(NDC)(bpy)(H2O)]2+ coordination units. The syn-syn-η1:η1 linear polymeric conformation exist in the 1D coordination polymer with adjacent Cu...Cu distance is 6.849 Å. A chain of cyclic tetrameric water clusters is present between the stacked layers of the 3D supramolecular structure. The formation of the 3D supramolecular structure is guided by various weak interactions such as O–H...O, C–H...O, C–H...π and π...π interactions. The coordination polymer 2 forms 3D supramolecular architecture guided by various weak interactions such as O–H...O, C–H...O and N–H...O interactions. The crystal structures of both coordination polymers have been determined using single crystal X-ray diffraction and their structural features are described. [ABSTRACT FROM AUTHOR]

A series of dinuclear metallacycles of Mn(II), Co(II), Ni(II), Cu(II) and Cd(II) with 1,8-naphthalene dicarboxylic acid (H2NDC) with co-ligand such as 2,2′-bipyridine (bpy) or solvent molecules have been synthesized in a refluxed condition. One mononuclear Ni(II) complex has also been synthesized following the same synthetic procedure with NDC, bpy and pyridine. Among them two polymorphic structures have been isolated. The single crystal X-ray structures of all the metallacycles have been described along with Hirshfield surface analysis. [ABSTRACT FROM AUTHOR]

An Erratum to this paper has been published: https://doi.org/10.1134/S002247662309010X [ABSTRACT FROM AUTHOR]

Current research issues in the development of efficient analysis models and their efficient numerical implementation for smart piezoelectric laminated structures are discussed in this paper. The improved zigzag theories with a layerwise quadratic variation of electric potential have emerged as the best compromise between accuracy and cost for hybrid composite, sandwich and FGM beams and plates. The concept of associating surface potentials to electric nodes and internal potentials to physical nodes is very effective in modeling the equipotential electroded surfaces. Unified formulations for shear and extension mode actuation, and modeling of piezoelectric composite actuators and sensors are discussed. Future challenge lies in developing efficient theories capable of predicting the interlaminar transverse shear stresses in hybrid laminates directly from the constitutive equations. [ABSTRACT FROM AUTHOR]

An efficient global zigzag theory (GZIGT) is developed for elastic laminated plates, by approximating the in-plane displacements by a cubic expansion in thickness coordinate along with a global zigzag function, which takes values ±1 at successive interfaces. The deflection is approximated to account explicitly for transverse thermal strain. The displacement variables are reduced to five, the same as used in first-order shear deformation theory, by imposing the conditions on transverse shear at three a priori selected interfaces/faces. A third order theory (TOT1) is also developed with similar expression of deflection. GZIGT and TOT1 are assessed by comparison with exact three-dimensional solutions for simply-supported square plates for sinusoidal pressure and thermal loads, natural frequencies and buckling. In general, GZIGT yields good results for two-ply, three-ply and four-ply composite plates, but it is inaccurate for a highly inhomogeneous test plate. [ABSTRACT FROM AUTHOR]

An improved efficient zigzag theory (IZIGT) and an improved third order theory (ITOT) are presented for laminated circular cylindrical shells and shell panels under thermal loading. The transverse deflection is approximated nonuniformly to explicitly account for the transverse strain due to temperature. The inplane displacements are modelled in ITOT to have global cubic variation across the thickness and are modelled in IZIGT to have additional layerwise zigzag linear variation. The number of primary variables is reduced to 5 by imposing conditions on transverse shear at outer and inner surfaces for ITOT and also at layer interfaces for IZIGT. The governing equations and boundary conditions are derived using the principle of virtual work. The IZIGT, ZIGT, ITOT and TOT are assessed in comparison with exact 3D thermoelasticity solution for simply supported shells and shell panels of different lay-ups. The comparison reveals that IZIGT and ITOT are an improvement over ZIGT and TOT respectively, and in general, IZIGT is more accurate than ITOT for thermal loading. [ABSTRACT FROM AUTHOR]