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One mono-nuclear Ni(II) complex [NiL(CH3COO)] (1) and one di-nuclear Cu(II) complex, [Cu2L2(CH3-COO)2] (2), with pendant and bridging acetate moieties, respectively, have been synthesized using a novel N,N,O donor Schiff base ligand HL, 1-(((piperidine-2-ylmethyl)imino)methyl)naphthalene-2-al, prepared by the simple condensation of 2-hydroxy-1-naphthaldehyde and 2-amino methyl piperidine. With the aid of numerous spectroscopic studies, the three compounds described above have been properly characterized. The single crystal data analyses of both the complexes reveal that in complex 1, one deprotonated ligand, one pendant acetate ion, and one Ni(II) ion form a mononuclear distorted square planar geometry and in complex 2, each Cu(II) center connects with one deprotonated ligand and a double m1.1-acetato-bridge forming a distorted trigonal bipyramidal geometry, while two acetate bridges connect two Cu(II) centers forming a dinuclear complex. After rigorous characterization, both the complexes are investigated to check their binding efficacy with biomacromolecules like DNA and HSA, and the results, obtained from a variety of biophysical studies like absorption, fluorescence, and circular dichroism-based titrations, clearly disclose that both the complexes have an affinity for binding with DNA and HSA. Fluorescence displacement analysis and a DNA melting study demonstrate different modes of binding for the two complexes with the DNA host, namely intercalative mode associated with groove binding for complex 1 and only groove binding for complex 2. Circular dichroism spectral analysis of HSA during interaction with the complexes confirms some structural changes in HSA upon binding. Determination of the thermodynamic parameters implies the binding interactions of HSA with the two complexes to be spontaneous. After a convincing study of the complex--biomacromolecule binding interactions, an MTT assay study on both cancer and normal cells reveals that of the two complexes, complex 2 is the better one, showing superior anticancer properties together with low toxicity to a normal cell. Finally, an apoptotic cell-killing pathway of the studied complexes has been confirmed by a nuclear staining study. [ABSTRACT FROM AUTHOR]

The formation and the stability of a unique intermetallic phase Rh2Cd5 (2:5) that adopts a defect In3Pd5 structure type, has been addressed on the basis of electronic structure calculation and chemical bonding approach. The crystal structures of three closely related phases {RhCd, Rh2Cd5 and Rh3Cd5−δ (δ ∼ 0.56)} in the Rh–Cd binary system are compared. Electronic structure calculations for all these phases reveal that a state-deficient region or pseudogap is opened up near the Fermi level in the electronic density of states. [ABSTRACT FROM AUTHOR]

The newly synthesized ultralow thermal conducting Cu4TiSe4 undergoes a temperature‐induced reversible structural phase transition at −92 °C. The room temperature structure exhibits cubic symmetry (space group P4‾ 3 m with lattice parameter a=5.6458(1) Å) and shows positional disorder in two Cu‐sites (4e and 1a Wyckoff sites). In this report, a structural study was carried out on the same sample by means of single‐crystal X‐ray diffraction data (nitrogen‐cryostat) collected at 131 K. At this temperature, Cu4TiSe4 crystallizes in rhombohedral symmetry, space group R3 m, with a=7.9538(5) Å and c=19.4828(17) Å. The low temperature structure is fourfold twinned. In the low temperature phase, copper atoms at 9b and 3a Wyckoff sites (originally 4e and 1a Wyckoff sites in the room temperature structure) order partially in comparison to room temperature structure. This temperature induced phase transition induce slight increase of the thermal conductivity of the material. [ABSTRACT FROM AUTHOR]

The newly synthesized ultralow thermal conducting Cu4TiSe4 undergoes a temperature‐induced reversible structural phase transition at −92 °C. The room temperature structure exhibits cubic symmetry (space group P4‾ 3 m with lattice parameter a=5.6458(1) Å) and shows positional disorder in two Cu‐sites (4e and 1a Wyckoff sites). In this report, a structural study was carried out on the same sample by means of single‐crystal X‐ray diffraction data (nitrogen‐cryostat) collected at 131 K. At this temperature, Cu4TiSe4 crystallizes in rhombohedral symmetry, space group R3 m, with a=7.9538(5) Å and c=19.4828(17) Å. The low temperature structure is fourfold twinned. In the low temperature phase, copper atoms at 9b and 3a Wyckoff sites (originally 4e and 1a Wyckoff sites in the room temperature structure) order partially in comparison to room temperature structure. This temperature induced phase transition induce slight increase of the thermal conductivity of the material. [ABSTRACT FROM AUTHOR]

Ultralow thermal conductivity draws great attention in a variety of fields of applications such as thermoelectrics and thermal barrier coatings. Herein, the crystal structure and transport properties of Cu4TiSe4 are reported. Cu4TiSe4 is a unique example of a non‐toxic and low‐cost material that exhibits a lattice ultra‐low thermal conductivity of 0.19 Wm−1 K−1 at room temperature. The main contribution to the unusually low thermal conductivity is connected with the atomic lattice and its dynamics. This ultralow value of lattice thermal conductivity (kL) can be attributed to the presence of the localized modes of Cu, which partially hybridize with the Se atoms, which in turn leads to avoidance of crossing of acoustic phonon modes that reach the zone boundary with a reduced frequency. Like a phonon glass electron crystal, Cu4TiSe4 could also open a route to efficient thermoelectric materials, even, with chalcogenides of relatively high electrical resistivity and a large band gap, provided that their structures offer a sublattice with lightly bound cations. [ABSTRACT FROM AUTHOR]

Ultralow thermal conductivity draws great attention in a variety of fields of applications such as thermoelectrics and thermal barrier coatings. Herein, the crystal structure and transport properties of Cu4TiSe4 are reported. Cu4TiSe4 is a unique example of a non‐toxic and low‐cost material that exhibits a lattice ultra‐low thermal conductivity of 0.19 Wm−1 K−1 at room temperature. The main contribution to the unusually low thermal conductivity is connected with the atomic lattice and its dynamics. This ultralow value of lattice thermal conductivity (kL) can be attributed to the presence of the localized modes of Cu, which partially hybridize with the Se atoms, which in turn leads to avoidance of crossing of acoustic phonon modes that reach the zone boundary with a reduced frequency. Like a phonon glass electron crystal, Cu4TiSe4 could also open a route to efficient thermoelectric materials, even, with chalcogenides of relatively high electrical resistivity and a large band gap, provided that their structures offer a sublattice with lightly bound cations. [ABSTRACT FROM AUTHOR]

Ultralow thermal conductivity draws great attention in a variety of fields of applications such as thermoelectrics and thermal barrier coatings. Herein, the crystal structure and transport properties of Cu4TiSe4 are reported. Cu4TiSe4 is a unique example of a non‐toxic and low‐cost material that exhibits a lattice ultra‐low thermal conductivity of 0.19 Wm−1 K−1 at room temperature. The main contribution to the unusually low thermal conductivity is connected with the atomic lattice and its dynamics. This ultralow value of lattice thermal conductivity (kL) can be attributed to the presence of the localized modes of Cu, which partially hybridize with the Se atoms, which in turn leads to avoidance of crossing of acoustic phonon modes that reach the zone boundary with a reduced frequency. Like a phonon glass electron crystal, Cu4TiSe4 could also open a route to efficient thermoelectric materials, even, with chalcogenides of relatively high electrical resistivity and a large band gap, provided that their structures offer a sublattice with lightly bound cations. [ABSTRACT FROM AUTHOR]

Ultralow thermal conductivity draws great attention in a variety of fields of applications such as thermoelectrics and thermal barrier coatings. Herein, the crystal structure and transport properties of Cu4TiSe4 are reported. Cu4TiSe4 is a unique example of a non‐toxic and low‐cost material that exhibits a lattice ultra‐low thermal conductivity of 0.19 Wm−1 K−1 at room temperature. The main contribution to the unusually low thermal conductivity is connected with the atomic lattice and its dynamics. This ultralow value of lattice thermal conductivity (kL) can be attributed to the presence of the localized modes of Cu, which partially hybridize with the Se atoms, which in turn leads to avoidance of crossing of acoustic phonon modes that reach the zone boundary with a reduced frequency. Like a phonon glass electron crystal, Cu4TiSe4 could also open a route to efficient thermoelectric materials, even, with chalcogenides of relatively high electrical resistivity and a large band gap, provided that their structures offer a sublattice with lightly bound cations. [ABSTRACT FROM AUTHOR]

γ1‐AuZn2.1 in the Au–Zn binary system has been synthesized and its structure analyzed by single‐crystal X‐ray diffraction. It crystallizes in the trigonal space group P31m (No. 157) with ∼227 atoms per unit cell and represents a 3a × 3a × c superstructure of rhombohedrally distorted γ‐Au5–xZn8+y. The structure is largely tetrahedrally closed packed. The formation of γ1‐AuZn2.1 can be understood within the framework of a Hume‐Rothery stabilization mechanism with a valence electron concentration of 1.68 e/a (valence electrons per atom). [ABSTRACT FROM AUTHOR]

A nonstoichiometric line phase, Rh 3 Cd 5-δ (δ ∼ 0.56), is found in close vicinity to RhCd and structurally characterized by single-crystal X-ray diffraction and energy-dispersive X-ray spectroscopy. The compound crystallizes in the cubic space group Im 3 m (No. 229) with lattice constant a = 6.3859(9) Å and represents a 2 × 2 × 2 superstructure of RhCd, which accommodates a vacancy concentration of nearly 6% in its crystal structure. The first-principles electronic structure calculation on a hypothetical ordered configuration of Rh 3 Cd 5-δ reveals that Rh-Cd heteroatomic interaction plays a major role in the stability of the compound. A combination of the total energy, formation energy, and crystal orbital Hamilton population calculations on hypothetical model configurations establishes that the compound upholds an optimum vacancy concentration in the Cd2a (Cd1) site for the stability of the phase.

Ultralow thermal conductivity draws great attention in a variety of fields of applications such as thermoelectrics and thermal barrier coatings. Herein, the crystal structure and transport properties of Cu 4 TiSe 4 are reported. Cu 4 TiSe 4 is a unique example of a non-toxic and low-cost material that exhibits a lattice ultra-low thermal conductivity of 0.19 Wm -1  K -1 at room temperature. The main contribution to the unusually low thermal conductivity is connected with the atomic lattice and its dynamics. This ultralow value of lattice thermal conductivity (k L ) can be attributed to the presence of the localized modes of Cu, which partially hybridize with the Se atoms, which in turn leads to avoidance of crossing of acoustic phonon modes that reach the zone boundary with a reduced frequency. Like a phonon glass electron crystal, Cu 4 TiSe 4 could also open a route to efficient thermoelectric materials, even, with chalcogenides of relatively high electrical resistivity and a large band gap, provided that their structures offer a sublattice with lightly bound cations., (© 2020 Wiley-VCH GmbH.)

γ 1 -AuZn 2.1 in the Au-Zn binary system has been synthesized and its structure analyzed by single-crystal X-ray diffraction. It crystallizes in the trigonal space group P31m (No. 157) with ∼227 atoms per unit cell and represents a \surd3a × \surd3a × c superstructure of rhombohedrally distorted γ-Au 5-x Zn 8+y . The structure is largely tetrahedrally closed packed. The formation of γ 1 -AuZn 2.1 can be understood within the framework of a Hume-Rothery stabilization mechanism with a valence electron concentration of 1.68 e/a (valence electrons per atom).