Synthesis, crystal structure and luminescence of [(CH₃)₃S]₂ZrCl₆

The current work reports on the synthesis, crystal structure and optoelectronic properties of (Me3S)2ZrCl6, prepared by reacting the solid precursors (Me3S)Cl and ZrCl4 in pyrex tubes at 150 °C under vacuum. According to X-ray powder diffraction and Rietveld analysis, (Me3S)2ZrCl6 crystallizes in the cubic space group Pa-3 (No. 205) with a = 12.4664(1) Å. The crystal structure consists of isolated trigonal pyramidal trimethylsulfonium cations and octahedral [ZrCl6]2- anions with weak hydrogen bonds among them and no signs of structural disorder. This 0D-material is stable in air and dissolves in water and dimethylformamide. Raman spectroscopy shows characteristic vibrational modes for the organic and inorganic moieties over the frequency range of 5–3200 cm−1. UV-Vis spectroscopy reveals a large band gap of 5.1 eV and a broadband luminescence with emission maximum at 465 nm in the solid state. The luminescent properties of (Me3S)2ZrCl6 are discussed and compared with those of similar inorganic or metal-organic compounds.</p

Dynamic versus Static Character of the Magnetic Jahn–Teller Effect: Magnetostructural Studies of [Fe₃O(O₂CPh)₆(py)₃]ClO₄·py

Complex [Fe₃O­(O₂CPh)₆(py)₃]­ClO₄·py (<b>1</b>) crystallizes in the hexagonal <i>P</i>6₃/<i>m</i> space group, and its cation exhibits a crystallographically imposed <i>D</i>_3<i>h</i> symmetry due to a <i>C</i>₃ axis passing through the oxide of its {Fe₃O}⁷⁺ core. Single-crystal unit-cell studies carried out with synchrotron radiation confirmed that this symmetry is retained down to 4.5 K; a full crystal structure determination carried out at 90 K resolved the previously reported disorder of the perchlorate anion. Magnetic susceptibility and electron paramagnetic resonance (EPR) data for complex <b>1</b> were interpreted with a model considering the retention of the threefold crystallographic symmetry while predicting a lowering of the magnetic symmetry. This model considered the effects of atomic vibrations of the central oxide on the magnetic properties of the complex by incorporating these movements into the spin Hamiltonian through angular overlap considerations of the atomic orbitals; no ad hoc magnetic Jahn–Teller effect was considered. The derived magnetostructural correlations achieved an improvement in the interpretation of the magnetic susceptibility data using the same number of free variables. They also improved the simulations of the EPR data, which exhibit a complicated set of at least five axial resonances; improved simulations were achieved using only two spectral components. Due to the thermal effects on the oxide vibrations, the model predicts a temperature dependence of the magnetic coupling <i>J</i>, which should not be viewed as a constant but as a variable

Dynamic versus Static Character of the Magnetic Jahn–Teller Effect: Magnetostructural Studies of [Fe₃O(O₂CPh)₆(py)₃]ClO₄·py

Complex [Fe₃O­(O₂CPh)₆(py)₃]­ClO₄·py (<b>1</b>) crystallizes in the hexagonal <i>P</i>6₃/<i>m</i> space group, and its cation exhibits a crystallographically imposed <i>D</i>_3<i>h</i> symmetry due to a <i>C</i>₃ axis passing through the oxide of its {Fe₃O}⁷⁺ core. Single-crystal unit-cell studies carried out with synchrotron radiation confirmed that this symmetry is retained down to 4.5 K; a full crystal structure determination carried out at 90 K resolved the previously reported disorder of the perchlorate anion. Magnetic susceptibility and electron paramagnetic resonance (EPR) data for complex <b>1</b> were interpreted with a model considering the retention of the threefold crystallographic symmetry while predicting a lowering of the magnetic symmetry. This model considered the effects of atomic vibrations of the central oxide on the magnetic properties of the complex by incorporating these movements into the spin Hamiltonian through angular overlap considerations of the atomic orbitals; no ad hoc magnetic Jahn–Teller effect was considered. The derived magnetostructural correlations achieved an improvement in the interpretation of the magnetic susceptibility data using the same number of free variables. They also improved the simulations of the EPR data, which exhibit a complicated set of at least five axial resonances; improved simulations were achieved using only two spectral components. Due to the thermal effects on the oxide vibrations, the model predicts a temperature dependence of the magnetic coupling <i>J</i>, which should not be viewed as a constant but as a variable

Spin-Relaxation Properties of a High-Spin Mononuclear Mn^IIIO₆‑Containing Complex

The magnetic properties of the mononuclear manganese­(III) complex [Mn­{(OPPh₂)₂N}₃] are investigated by means of magnetometry and dual-mode X-band electron paramagnetic resonance spectroscopy. Slow relaxation of magnetization is induced in the presence of external magnetic fields

Spin-Relaxation Properties of a High-Spin Mononuclear Mn^IIIO₆‑Containing Complex

The magnetic properties of the mononuclear manganese­(III) complex [Mn­{(OPPh₂)₂N}₃] are investigated by means of magnetometry and dual-mode X-band electron paramagnetic resonance spectroscopy. Slow relaxation of magnetization is induced in the presence of external magnetic fields

A [24-MC-6] Zinc Metallacoronate with a Nonsteroidal Antiinflammatory Drug as the Constructing Ligand

The interaction of ZnCl₂ with 2-dipyridylketonoxime (=Hpko) and flufenamic acid (=Hfluf) in a basic methanolic solution leads to the formation of a hexanuclear 24-membered metallacoronate, [Zn₆(OH)₂(pko)₄(fluf)₆] (<b>1</b>), with a [Zn–O–C–O] repeat unit and a nonsteroidal antiinflammatory drug as the constructing ligand. Compound <b>1</b> retains its structure in a dimethyl sulfoxide solution, as shown by ¹H NMR spectroscopy and molar conductance

Ni^II₂₀ “Bowls” from the Use of Tridentate Schiff Bases

The reactions of <i>N</i>-salicylidene-<i>o</i>-aminophenol or its derivatives and excess of nickel­(II) acetate in alcohols have led to Ni^II₂₀ clusters with an unprecedented “bowl” metal topology

Nonemployed Simple Carboxylate Ions in Well-Investigated Areas of Heterometallic Carboxylate Cluster Chemistry: A New Family of {Cu^II₄Ln^III₈} Complexes Bearing <i>tert</i>-Butylacetate Bridging Ligands

The first use of <i>tert</i>-butylacetate as bridging ligand in 3d/4f-metal cluster chemistry, in conjunction with the versatile chelate ligand pyridine-2,6-dimethanol, has afforded a new family of [Cu₄Ln₈(OH)₆­(NO₃)₂­(O₂CCH₂Bu<i>^t</i>)₁₆­(pdm)₄] clusters with unprecedented structures and slow magnetization relaxation for the {Cu^II₄Dy^III₈} member. The molecular structure of representative complex <b>1</b> consists of a {Cu^II₄Gd^III₈} cage-like cluster built from two {CuGd₃} cubanes which are linked to each other and to two {CuGd} subunits on opposite sides through two η²:η²:η²:μ₅ NO₃^– ions. The metal ions are additionally bridged by μ₃-OH^–, μ₃-OR^–, and μ-OR^– groups to give an overall [Cu₄Gd₈­(μ₅-NO₃)₂­(μ₃-OH)₆­(μ₃-OR)₂­(μ-OR)₈]¹⁴⁺ core. Peripheral ligation about the core is provided by the N,O,O-chelating part of the pdm^2– groups and, more impressively, by the oxygen atoms of 16 bridging Bu<i>^t</i>CH₂CO₂^– ligands; the latter are arranged into five classes, adopting a total of six different binding modes with the metal centers. The combined work demonstrates the ligating flexibility of <i>tert</i>-butylacetate ion and its usefulness in the synthesis of new 3d/4f-metal cluster compounds

Ni^II₂₀ “Bowls” from the Use of Tridentate Schiff Bases

The reactions of <i>N</i>-salicylidene-<i>o</i>-aminophenol or its derivatives and excess of nickel­(II) acetate in alcohols have led to Ni^II₂₀ clusters with an unprecedented “bowl” metal topology

Structural–Spectrochemical Correlations of Variable Dimensionality Crystalline Metal–Organic Framework Materials in Hydrothermal Reactivity Patterns of Binary–Ternary Systems of Pb(II) with (a)Cyclic (Poly)carboxylate and Aromatic Chelator Ligands

Efforts to comprehend the structural–spectrochemical correlations of crystalline metal–organic framework materials of Pb­(II) with (a)­cyclic and aromatic chelators linked to photoluminescent applications led to the hydrothermal pH-specific synthesis of crystalline materials [Pb­{H₂BTC}­(phen)­(H₂O)]_<i>n</i>·2<i>n</i>H₂O­(<b>1</b>), [Pb₂{CBTC}]_<i>n</i>(<b>2</b>), [Pb₄(phen)₈{CBTC}₂(H₂O)₄]₃·70.3H₂O­(<b>3</b>), and [Pb­{HCTA}­(H₂O)₂]_<i>n</i>·<i>n</i>H₂O­(<b>4</b>). X-ray studies showed that <b>1</b>–<b>4</b> exhibit unique architectures linked to 2D–3D coordination polymers formulated by Z-type units composed of Pb₂O₂ cores, unusually high number of lattice–water molecules, and π–π and H-bond interactions. The contribution of the nature–structure properties of the aliphatic-(a)­cyclic organic (poly)­carboxylic/aromatic chelators-ligands to binary-ternary Pb­(II) reactivity weaves into the assembly of supramolecular networks, thereby providing clear structural–spectroscopic inter-relationships exemplifying the observed photoluminescent activity in a distinct MOF-linked fashion