Mononuclear and heterodinuclear phenanthrolinedione complexes of <Emphasis Type="Italic">d</Emphasis>- and <Emphasis Type="Italic">f</Emphasis>-block elements

1,10-Phenanthroline-5,6-dione (Phd) complexes of group 3 and lanthanide elements having formulae Ln(hfac)₃(Phd) (Ln = Y, Eu, Yb; hfac = hexafluoroacetylacetonate) were synthesised and characterised. Complexes of d-block elements of the type [MCl(Phd)(p-cymene)]⁺ (M = Ru, Os) were also prepared. In all these species, coordination of the polydentate ligand occurs by the N-donor moieties, as indicated by DFT calculations. The novel compounds were tested, together with fac-ReBr(Phd)(CO)₃, as precursors for the preparation of heterobimetallic d/f derivatives. The reaction of the rhenium complex with yttrium or lanthanide anhydrous triflate salts led to the formation of the complexes ReBr(CO)₃(N,N′-Phd-O,O′)Ln(OTf)₃(THF) (Ln = Y, Eu, Yb), where the trivalent ions interacted with the quinonoid moiety. The redox properties of the rhenium centre were strongly affected by the coordination of Ln(OTf)₃, as observed by comparing the cyclic voltammetry measurements carried out on fac-ReBr(Phd)(CO)₃ and on ReBr(CO)₃(N,N′-Phd-O,O′)Y(OTf)₃.     

Synthesis and crystal structure of two complexes [Cu<Subscript>2</Subscript>(NiL)<Subscript>2</Subscript>Cl<Subscript>4</Subscript>] and [Cd<Subscript>2</Subscript>(CuL)<Subscript>2</Subscript>Cl<Subscript>4</Subscript>]

Macrocyclic and supermolecular complexes [Cu₂(NiL)₂Cl₄] (I) and [Cd₂(CuL)₂Cl₄] (II) (H₂L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) have been synthesized and structurally determined by X-ray diffraction and IR spectrum. Complex I crystallizes in the monoclinic system with P2₁/n group, a = 10.9019(15), b = 14.3589(19), c = 12.4748(17) 0A, β = 108.645(2)°, Z = 4. Complex II crystallizes in the monoclinic system with P2₁/n group, a = 10.9784(16), b = 14.580(2), c = 12.8904(18) Å, β = 109.339(2)°, Z = 4.     

Structure of A Coordination Polymer [Cu(En)<Subscript>2</Subscript>CrO<Subscript>4</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>

The crystal structure of [Cu(En)₂CrO₄]_n (En is ethylenediamine) is determined: a = 14.7359(4) Å, b = 9.8083(3) Å, c = 14.2664(4) Å, V = 2061.98(10) ų, space group Cmce, Z = 8, d_x = 1.931 g/cm³. It is demonstrated that the studied phase is isostructural with [Сu(Еn)₂SO₄]_n. A pseudotetragonal copper atom coordination (Cu–N 2.0204 Å and 2.0244 Å, ∠N–Cu–N 84.73°) is completed to distorted octahedral by two oxygen atoms of chromate anions (Cu–O 2.433 Å and 2.380 Å).     

Study of variation in thermophysical properties of RE<Subscript>6</Subscript>UO<Subscript>12</Subscript>(s) along the lanthanide series

The novel ligand N,N,N′′′′,N′′′′-tetrabutyl-N′′′,N′′′-(N″,N″-diethyl)-ethidene bisdiglycolamide (TBEE-BisDGA) and other eight analogous extractants have been synthesized and characterized by NMR and HRMS. The solvent extraction of Th⁴⁺, UO₂ ²⁺ and Eu³⁺ from nitric acid solution using the above BisDGA extractants was investigated in 1-dodecanol at 30 ± 1 °C. The extractants exhibited higher affinity toward Th⁴⁺ than UO₂ ²⁺ and Eu³⁺ in the present system. The maximum value of separation factor SF _Th(IV)/U(VI) and SF _{Th(IV)/Eu(III)} is 78.5 and 53.3 respectively for TBEE-BisDGA, 88.1 and 69.5 respectively in the case of TB ^i-PE-BisDGA at 3 M HNO₃ solution.     

Crystal structure and triboluminescence of centrosymmetric complex [Eu(NO<Subscript>3</Subscript>)<Subscript>3</Subscript>(HMPA)<Subscript>3</Subscript>]

By single crystal X-ray analysis, the atomic structure of the crystals of [Eu(NO₃)₃(HMPA)₃] complex (HMPA is hexamethylphosphorotriamide) possessing intense triboluminescence is determined. Symmetry of centrosymmetrical crystals is monoclinic: a = 13.785(1) Å, b = 19.746(2) Å, c = 14.723(1) Å, β= 102.143(2)°, P2₁/n space group, Z = 4, d _x = 1.484 g/cm³. The crystal structure is represented by separate C₁₈H₅₄EuN₁₂O₁₂P₃ complexes linked by van der Waals interactions with pronounced cleavage planes. The coordination polyhedron of Eu(III) atom reflects the state of distorted square antiprism. The possible causes of spectral differences in the Stark structure of photo- and triboluminescence are discussed.     

Synthesis and magnetic properties of quasi-unidimensional oxide Sr<Subscript>6.3</Subscript>Rh<Subscript>2.35</Subscript>Mn<Subscript>2.35</Subscript>O<Subscript>15</Subscript>

Attempts of the synthesis in air of complex oxides Sr₃RhMnO_x and Sr₄Rh_1.5Mn_1.5O_x resulted in revealing formation of a new oxide phase Sr_6.3Rh_2.35Mn_2.35O₉ related to quasi-unidimensional family A_3n+3m A′ _n B_3m+n O_9m+6n at n = 1 and m = 1. Its structural characteristics and magnetic properties are studied. X-ray data of the obtained phase is indicated on the basis of trigonal cell (spatial group P321) with the parameters: a 9.6239(4) Å; c ₁ 4.1130(4) Å, c ₂ 2.4946(2) Å. Manganese and rhodium exist in the compound as the cations Mn⁴⁺, Rh³⁺ and Rh⁴⁺, as follows from the data of measuring of magnetic susceptibility in the range 2–300 K.     

The molecular designs and properties of asymmetric heterocycles (HBrBN<Subscript>3</Subscript>)<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> (<Emphasis Type="Italic">n</Emphasis> = 1-4)

The structures and properties of asymmetric heterocycles (HBrBN₃) _n (n = 1-4) are systematically studied at the B3LYP/6-31G* level. The molecules (HBrBN₃) _n (n = 2-4) have the core structures of a 2n-membered ring with alternating boron and α-nitrogen atoms. The relationships between geometrical parameters and oligomerization degree n are discussed. The calculated IR spectra have four main characteristic regions. Trends in thermodynamic properties with temperature and oligomerization degree n are discussed. Thermodynamic analysis of the gas-phase oligomerizations shows that formation of the most stable heterocycles (HBrBN₃) _n (n = 2-4) is enthalpy driven in the range of 200-800 K.     

A Systematic Search for Structures and Stabilities of Asymmetric Clusters (HfInN<Subscript>3</Subscript>)<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> (<Emphasis Type="Italic">n</Emphasis> = 1-6)

In order to find single source precursors (SSP), the structures, relative stabilities, and IR spectra of small asymmetric clusters (HFInN₃) _n (n = 1–6) are systematically investigated by means of the density functional theory at the B3LYP level. The obtained geometries show that the frameworks of clusters (HFInN₃) _n (n = 2–6) prefer to be 2n-membered ring with alternating indium and α-nitrogen atoms. The averaged binding energies reveal that all of asymmetric clusters (HFInN₃) _n (n = 1–6) can continue to gain energy as the cluster size n increasing. The second-order difference of energy (Δ₂E) and the HOMO-LUMO energy gap (E_gap) as a function of the cluster size n both exhibit a pronounced even-odd alternation phenomenon. The influences of cluster size n and temperature T on the thermodynamic properties of clusters are discussed. Judged by enthalpies and Gibbs free energies, the formations of the most stable clusters (HFInN₃) _n (n = 2–6) from the monomer are thermodynamically favorable in the range of 200–800 K.     

Syntheses and crystal structures of [Bi(DMSO)<Subscript>8</Subscript>][Fe(NCS)<Subscript>6</Subscript>] and [Al(DMSO)<Subscript>6</Subscript>][Al(NCS)<Subscript>6</Subscript>]

New complexes of composition [Bi(DMSO)₈][Fe(NCS)₆] (1) and [Al(DMSO)₆][Al(NCS)₆] (2) have been prepared, and an octahedral hexarodanoaluminate anion has been structurally characterized for the first time. Crystals of compound 1 are triclinic, space group \(P\bar 1\), a = 11.2368(4) Å, b = 11.4063(4) Å, c = 21.0711(9) Å, α = 92.9520(10)°, β = 99.9430(10)°, γ = 111.9290(10)°, V = 2447.69(16) ų, Z = 2, ρ_calc = 1.680 g/cm³, R ₁ = 0.0564; crystals of compound 2 are cubic, space group \(Pa\bar 3\), a = 15.8201(4) Å, V = 3959.39(17) ų, Z = 4, ρ_calc = 1.462 g/cm³, R ₁ = 0.0475. The bismuth coordination polyhedron BiO₈ in compound 1 is a distorted square antiprism with broken square faces (Bi-O, 2.368-2.582 Å). In the structure of 2, the cation disordered in a complex manner has an octahedral configuration (Al-O, 1.888(11)-1.912(11) Å).     

Supramolecular 2D structure of [Co(2-Me-Pyz)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>4</Subscript>](NO<Subscript>3</Subscript>)<Subscript>2</Subscript>

The complex [Co(2-Me-Pyz)₂(H₂O)₄](NO₃)₂ is synthesized and its structure is determined. The crystals are monoclinic: space group P2₁/n, a = 10.685(2) Å, b = 6.837(1), c = 12.515(3) Å, β = 91.84(3)°, V = 913.8(3) ų, ρ_calcd = 1.042 g/cm ³, Z = 2. The Co²⁺ ion (in the inversion center) is coordinated at the vertices of the distorted octahedron by two nitrogen atoms of methylpyrazine and four oxygen atoms of the water molecules (Co(1)–N(1) 2.180(3), average Co(1)–O(w) 2.079(3) Å, angles at the Co atom 87.9(1)–92.1(1)°). Supramolecular pseudometallocycles are formed in the structure through the O(w)–H…N(1) hydrogen bonds between the coordinated H₂O molecules and the terminal nitrogen atoms of the 2-methylpyrazine molecules. Their interaction results in the formation of supramolecular layers joined by the NO₃ groups into a three-dimensional framework.     

Synthesis and X-ray investigation of Rb<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>] and Cs<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>]

Powder and single crystal X-ray diffraction studies have been performed for anhydrous nitrate complexes Rb₂[Pd(NO₃)₄] (I) and Cs₂[Pd(NO₃)₄] (II). Crystal data for I: a = 7.843(1) Å, b = 7.970(1) Å, c = 9.725(1) Å; β = 100.39(1)°, V = 597.9(1) Å ³, space group P2₁/c, Z = 2, d _calc = 2.918 g/cm³; for II: a = 10.309(2) Å, b = 10.426(2) Å, c = 11.839(2) Å; β = 108.17(3)°, V = 1209.0(4) ų, space group P2₁/c, Z = 4, d ^calc = 3.408 g/cm³. The structures are formed by isolated [Pd(NO₃)₄]^2? complex anions and alkali metal cations. The plane-square environment of the Pd atom is formed from the oxygen atoms of the monodentate nitrate groups. The geometrical characteristics of the complex anions are analyzed. Compound II has a short contact Pd...Cs 3.252 Å.     

Structure and characterization of a 1d double chain copper(II) complex {[Cu(BIX)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>](PhCOO)<Subscript>2</Subscript>}<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>

A novel copper(II) complex {[Cu(BIX)₂(H₂O)₂](PhCOO)₂} _n (1) (BIX = 1,4-bis(imidazole-1-methyl))-benzene) is synthesized and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic crystal system with the P-1 space group, Z = 1, a = 9.465(2) Å, b = 9.703(2) Å, c = 12.060(2) Å, α = 77.26(3)°, β = 70.37(3)°, γ = 67.14(3)°, and V = 956.1(3) ų. The crystal structural analysis of complex 1 shows that the copper center is six-coordinated in an elongated octahedral geometry by four N atoms from four different BIX and two O atoms from two water molecules; two neighboring Cu(II) cations are bridged by two BIX extending into an infinite 1D double chain structure.     

Synthesis and crystal structure of a 1D coordination polymer [Cd(NITpPy)<Subscript>2</Subscript>(N(CN)<Subscript>2</Subscript>)<Subscript>2</Subscript>)]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>

A novel one-dimensional chain complex [Cd(NITpPy)₂(N(CN)₂)₂)] _n (NITpPy = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and characterized structurally. It crystallizes in the triclinic space group P \(\bar 1\) with a = 7.1742(13), b = 9.4913(17), c = 13.208(2) Å, α = 71.020(2)°, β=87.308(2)°, γ = 70.503(2)°, V = 799.8(3) ų, C₂₈H₃₂CdN₁₂O₄, Mr = 713.06, Z = 1, ρ _c = 1.48 g/cm³, μ(MoK _α) = 0.736 mm^?1, F(000) = 364, R = 0.0275 and wR = 0.0605 for 2702 observed reflections with I > 2σ(I). The crystal structure consists of infinite chains of [Cd(NITpPy)₂(N(CN)₂)₂)] units linked by dicyanamide anions [N(CN)₂]^?. Each Cd²⁺ ion is six-coordinated with the geometry of a distorted octahedron.     

Crystal and molecular structures and luminescence properties of [Eu(Cin)<Subscript>3</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> complex

The crystal structure of europium cinnamate of the composition [Eu(Cin)₃] _n (Cin is cinnamic acid anion C₉H₇O ₂ ^? ) was determined by X-ray crystallography (a = 22.626(1) Å, c = 7.7330(7) Å, space group R3/c, Z = 3, ρ_calc = 1.448 g/cm³). The coordination polyhedron of Eu atoms is a distorted trigonal prism with three centered square faces. The structure is built of infinite polymeric chains [Eu(Cin)₃] _n running along the c axis and linked by van der Waals and π stacking interactions. Luminescent characteristics of the compound were determined.     

Structural investigation of [Au(en)<Subscript>2</Subscript>]Cl(ReO<Subscript>4</Subscript>)<Subscript>2</Subscript> and [Au(en)<Subscript>2</Subscript>](ReO<Subscript>4</Subscript>)<Subscript>3</Subscript> complexes

Novel complex salts [Au(en)₂]Cl(ReO₄)₂ (I) and [Au(en)₂](ReO₄)₃ (II), en = ethylenediamine, are obtained. Their crystal structures are determined by single crystal X-ray diffraction. Complex I crystallizes in the triclinic crystal system: a = 6.2172(7) Å, b = 7.1644(8) Å, c = 8.8829(8) Å, α = 96.605(4)°, β = 110.000(4)°, γ = 97.802(4)°, P-1 space group, Z = 1, d _x = 3.905 g/cm³; complex II crystallizes in the monoclinic crystal system: a = 15.244(2) Å, b = 7.6809(8) Å, c = 9.3476(12) Å, β = 127.004(3)°, C2 space group, Z = 4, d _x = 4.057 g/cm³.     

A Quantum Chemical Study of C<Subscript>60</Subscript>Cl<Subscript>30</Subscript>, C<Subscript>60</Subscript>(OH)<Subscript>30</Subscript> Molecules and Fe@C<Subscript>60</Subscript>(OH)<Subscript>30</Subscript> Endocomplex

(U)PBE0/cc-pVDZ method is used to study the structure of C₆₀Cl₃₀, C₆₀(OH)₃₀ molecules and Fe@C₆₀(OH)₃₀ endocomplex. The triplet state of the endocomplex is shown to be the lowest in energy among its four states corresponding to different spin multiplicities and positions of Fe nucleus within the fullerene cavity. This state is characterized by bonding between the iron atom and one of two benzenoid cycles of the carbon cage, six internuclear Fe–C distances (208 pm), and 1s²2s²2p⁶3s²3p⁶3d^7.24s^0.14p^0.3 electron configuration of iron with spin population of 2.36.     

X-ray diffraction study of CsZn<Subscript>2</Subscript>Br<Subscript>5</Subscript>

CsZn₂Br₅ crystals are studied by X-ray diffraction. The compound crystallizes in the monoclinic system with the unit cell parameters a = 6.8880(12) Å, b = 10.4703(19) Å, c = 6.5197(9) Å, β = 108.25°, V = 446.55 ų, ρ_calcd = 4.960 g/cm³. Refractive indices are n _p = 1.640 and n _p = 1.754.     

Crystal Structure of [UO<Subscript>2</Subscript>SO<Subscript>4</Subscript>{(CH<Subscript>3</Subscript>)HNCONH(CH<Subscript>3</Subscript>)}<Subscript>2</Subscript>]

The single crystals of [UO₂SO₄{(CH₃)HNCONH(CH₃)}₂] (I) were synthesized and studied by X-ray diffraction. The crystals are monoclinic, a = 6.847(1) Å, b = 14.259(3) Å, c = 14.297(3) Å, β = 93.451(4)°, space group P2₁/n, Z = 4. The main structural units of crystals I are ribbons whose composition coincides with the composition of the compound. The crystal chemical formula of the complex is AT³M ₂ ¹ (A = UO ₂ ²⁺ ).     

Synthesis and characterization of a new monophosphate (C<Subscript>6</Subscript>H<Subscript>16</Subscript>N<Subscript>2</Subscript>)(H<Subscript>2</Subscript>PO<Subscript>4</Subscript>)<Subscript>2</Subscript>

Chemical preparation, crystal structure, and NMR spectroscopy of a new trans-2,5-dimethylpiperazinium monophosphate are given. This new compound crystallizes in the triclinic system, with the space group P-1 and the following parameters: a = 6.5033(3), b = 7.6942(4), c = 8.1473(5) Å, α = 114.997(3), β = 92.341(3), γ = 113.136(3), V = 329.14(3) ų, Z = 1, and D_x = 1.565 g cm^?3. The crystal structure has been determined and refined to R = 0.030 and R _w(F ²) = 0.032 using 1558 independent reflections. The structure can be described as infinite [H₂PO₄] _n ^n? chains with (C₆H₁₆N₂)²⁺ organic cations anchored between adjacent polyanions to form columns of anions and cations running along the b axis. This compound has also been investigated by IR, thermal, and solid-state, ¹³C and ³¹P MAS NMR spectroscopies and Ab initio calculations.     

Quantum-chemical study of ytterbium fluorides and of complex F<Subscript>2</Subscript>YbF<Subscript>2</Subscript>CeF<Subscript>2</Subscript>

The structural parameters of the (²Σ⁺//C_∞v)-YbF, (¹A₁//C_2v)-YbF2, (²A₂^′//D_3h)-YbF₃, (¹Ag//D_2h)-YbF₂Yb, (¹Ag//C_2h)-FYbF₂YbF, (¹A₁//C_2v)-FYbF₂YbF, (¹A₁//C_2v)-YbF₂YbF₂, (³B_3u//D_2h)-F₂YbF₂YbF₂, (²A′//C_s)-FYbF₂YbF₂, and (³B₂//С_2v)-F₂YbF₂CeF₂ molecules have been determined. Disproportionation of ytterbium monofluoride (2YbF → YbF₂ + Yb + 0.46 eV) is less exothermic than dimerization (2YbF → YbF₂Yb + 2.10 eV). The bond energy of the ytterbium difluoride molecules in the trans dimer (2.93 eV) exceeds those in the cis dimer (2.86 eV) and the coaxial dimer (1.66 eV). Ytterbium trifluoride dimerizes exothermically (2.95 eV) without spin pairing. The dipole and quadrupole moments of the molecules as well as the charges and spin populations of the atoms and the valence electron configurations of the lanthanides have been calculated.