Interplay between aminoalcohols and trifluoroacetate ligands: Ba–Cu heterometallics or cocrystallization of homometallics?

Water-soluble chiral coordination polymers of Li+, Na+, K+, and Ba2+ with an anionic iron(III) complex of a L-threonine derivative and a significant red shift of visible spectra with Al3+ salt

Four salts of an anionic iron(III) bis-complex, [Fe(LL-thr)2]1-, were synthesized from water or methanol. H2LL-thr is a tridentate ligand derived from the L-threonine amino acid, and the cations used are Li+ (1), Na+ (2), K+ (3), and Ba2+ (4). Single-crystal X-ray diffraction showed that all the complexes are coordination polymers of different dimensionalities. The iron(III) complex binds to cations through its coordinated phenolate and non-coordinated carboxylate oxygen atoms. While Li+ forms a linear chain, all others have a pair of bridged cations intervening the iron(III) complexes. The 3D network of Ba2+ salt has a sizeable solvent-accessible space occupied by aquated chloride ions. The differences in circular dichroism (CD) spectra and significantly lower conductance values in water and methanol support partial retention of the polymeric nature in methanol. The visible spectra of 4 in methanol or water showed an ∼10 nm shift of the charge transfer bands from 3. However, the addition of Al3+ salt to 2 showed a significant colour shift. Further investigation confirmed that the colour shift is due to partial protonation of the complex with protons generated from salt hydrolysis. Most reports on visual aluminium detection consider aluminium's binding as the shift's source. The present results show that protonation due to hydrolysis of aluminium salt can skew the observation.

Aminoalcohols and benzoates-friends or foes? Tuning nuclearity of Cu(ii) complexes, studies of their structures, magnetism, and catecholase-like activities as well as performing DFT and TDDFT studies

The Cu(ii) complexes of varying nuclearity are synthesized, characterized and assessed for catecholase activities.

The synthesis and characterization of a hexanuclear copper–yttrium complex for deposition of semiconducting CuYO2–0.5Cu2O composite thin films

A new Cu–Y precursor was implemented for deposition of CuYO₂–0.5Cu₂O thin film for PEC studies.

Temperature-controlled Deposition of Copper(I) Oxide and Metallic Copper Nanostructures from Single-source Molecular Precursor

A simple method of depositing morphology- and phase-tailored thin films of copper(i) oxide and metallic copper from [Cu(dmae)(TFA)]4·CH2Cl2 (1), where dmae is N,N-dimethylaminoethanolato and TFA is trifluoroacetato, on glass substrates by aerosol-assisted chemical vapour deposition is demonstrated. The tetrameric precursor 1 was synthesized and its structure was determined by single-crystal X-ray crystallography. Precursor 1 was applied for the deposition of nanostructured thin films of copper(i) oxide and copper nanowires at 250 and 375°C respectively. The deposited thin films were characterized by powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray diffraction, and ultraviolet–visible spectroscopy. The results indicate that the phase and morphology of the deposited material are strongly dependent on deposition temperature. UV-vis studies reveal that copper(i) oxide films with a band gap of 2.48 eV may find possible applications in tandem photoelectrochemical devices as light-absorbing material.

Semiconducting composite oxide Y2CuO4–5CuO thin films for investigation of photoelectrochemical properties

Y₂CuO₄–5CuO composite thin films having a band gap of 1.82 eV and a photocurrent density of 9.85 μA cm⁻² at 0.8 V have been deposited from a solution of precursor 1 by AACVD.

Synthesis, crystal structure and luminescent properties of one coordination polymer of cadmium(II) with mixed thiocyanate and hexamethylenetetramine ligands

A novel Cd(II) coordination polymer [Cd(SCN)(2)(hmt)(1/2)(H(2)O)](2).H(2)O (hmt=hexamethylenetetramine) has been synthesized and characterized by IR, elemental analysis, TG technique and X-ray crystallography. Cd(II) atom has an distorted octahedral environment with an N(3)S(2)O donor set. Every six Cd(II) centers are linked by hmt and thiocyanato bridges to form a planar 2D coordination polymer containing hexagonal metallocyclic rings [Cd(6)(SCN)(8)(hmt)(2)]. A 2D layer structure is held together with its neighboring ones via a set of hydrogen-bonding interactions to form a 3D supramolecular structure. The luminescent properties of the title complex in the solid state were investigated.

Cubane Variations: Syntheses, Structures, and Magnetic Property Analyses of Lanthanide(III)−Copper(II) Architectures with Controlled Nuclearities

Starting from a molecular cubane [Cu(4)L(4)] (1, with LH(2) = 1,1,1-trifluoro-7-hydroxy-4-methyl-5-aza-hept-3-en-2-one), we successfully replaced one and then two copper(II) ions of the cubane core by lanthanide ions to elaborate new families of 3d-4f complexes. Here, we report the syntheses, crystal structures, magnetic properties, and theoretical description of the tetranuclear copper(II) complex [Cu(4)L(4)] (1, [Cu(4)]) together with original yttrium(III) and gadolinium(III) heterometallic derivatives: [YCu(3)L(3)(hfac)(3)](-) (2, [YCu(3)]); [GdCu(3)L(3)(hfac)(3)](-) (3, [GdCu(3)]); [Y(3)Cu(6)L(6)(OH)(6)(MeOH)(6)(H(2)O)(6)](3+) (4, [Y(3)Cu(6)]); [Gd(3)Cu(6)L(6)(OH)(6)(MeOH)(6)(H(2)O)(6)](3+) (5, [Gd(3)Cu(6)]). 1 crystallizes in the P2(1)/c monoclinic space group with a cubane-like structure and shows ferromagnetic behavior. 2 and 3 crystallize in the P triclinic space group and exhibit also cubane-like structures in which one copper(II) ion of the cubane core is substituted by one lanthanide ion. The magneto-structural correlations carried out on the yttrium(III) derivative reveal a spin frustration between the copper(II) ions that is retained in the gadolinium(III) analog (J approximately -30 cm(-1)). 4 and 5 crystallize in the C2/c monoclinic space group and result from the condensation of three {Ln(2)Cu(2)} cubane-like moieties giving rise to nonanuclear architectures. On the basis of the theoretical investigations, it is suggested that the electronic distribution on the yttrium(III) ion may influence the magnetic interaction between the copper(II) pairs. Indeed, the sign and magnitude of the Cu-Cu interaction extracted from 4 do not seem to be retained in 5. Thus, the introduction of lanthanide ions is likely to influence the nature of the Cu-Cu magnetic interactions in addition to their magnetic contribution. This work should contribute to improve the SMM synthesis strategy on the basis of the association of 3d and 4f ions.