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3D electron diffraction (3D ED)/Micro electron diffraction (MicroED) has extended the limits of crystallography by enabling the determination of three dimensional molecular structures from sub-μm microcrystals. However, 3D ED/microED measurements using current state-of-the-art electron microscopes require experts in both electron microscopy and crystallography making the method rather difficult for researchers who simply need structures. Here, we present a diffractometer specifically designed for 3D ED/microED and show how it works for determining crystal structures. The newly developed electron diffractometer will provide many researchers with an easy path to structure determination of crystals that are less than 1 μm in size. [ABSTRACT FROM AUTHOR]

Three novel materials (5CzICz, Cz2ICz and Cz3ICz), based on the indolo[3,2,1-jk]carbazole and 9H-carbazole building blocks, with high triplet energies (ET ＞ 2.80 eV) and good thermal stability (Tg ＞ 101 °C) were synthesized, characterized and applied as host materials in PhOLED devices. In course of the preparation of the materials, an improved protocol for the synthesis of the indolo[3,2,1-jk]carbazole moiety has been developed. The careful molecular design of the title compounds allowed to avoid excimer formation of the indolo[3,2,1-jk]carbazole subunits in thin films. Therefore, the improved molecular design broadened the applicability of indolo[3,2,1-jk]carbazole host materials and significantly enhanced the efficiency of PhOLED devices based on these derivatives compared to previously reported indolo[3,2,1-jk]carbazole based compounds. Accordingly, employing the newly developed materials red (CEmax: 32.7 cd A−1, PEmax: 31.0 lm W−1, EQEmax: 20.4%), green (CEmax: 81.0 cd A−1, PEmax: 87.4 lm W−1, EQEmax: 21.5%) and blue (CEmax: 35.5 cd A−1, PEmax: 39.9 lm W−1, EQEmax: 18.0%) PhOLED devices with a remarkably low efficiency roll-off at 1000 cd m−2 (Cz2ICz– red: 5%; green: 0%; blue: 6%) were fabricated. [ABSTRACT FROM AUTHOR]

The sequential interaction of preformed [Cu2(L1)2(THF)2] (where H2L1 is 1,1-(1,3-phenylene)-bis(4,4-dimethylpentane-1,3-dione incorporating a 1,3-phenylene linker between its two β-diketone domains) and [Cu2(L4)2]·2H2O (where H2L4 is 1,1-(4,4′-oxybiphenylene)-bis(4,4-dimethylpentane-1,3-dione) incorporating a flexible oxybiphenylene linkage between the two β-diketone groups) with the potentially difunctional aliphatic non-planar co-ligands, N-methylpiperazine (mpip), N,N′-dimethylpiperazine (dmpip) and 1,4-thiomorpholine (thiomorph) is reported. A series of extended molecular assemblies exhibiting a range of di- and tetranuclear assemblies were obtained and their X-ray structures determined. Dinuclear [Cu2(L1)2(mpip)2]·2mpip incorporates two 5-coordinate, square pyramidal metal centres as does tetranuclear [{Cu2(L1)2}2(dmpip)2]·2dmpip. In contrast, dinuclear [Cu2(L1)2(dmpip)4]·dmpip and [{Cu2(L1)2}2(thiomorph)4]·3thiomorph each contain two 5-coordinate and two 6-coordinate centres. Each of [Cu2(L4)2(THF)2]·2THF and Cu2(L4)2(mpip)2]·H2O incorporate only 5-coordinate metal centres, with the latter complex forming a one-dimensional hydrogen bonded ribbon-like structure directed along the crystallographic a-axis. In keeping with the documented tendency for the smallest, least strained assembly to form in supramolecular self-assembly processes, the incorporation of the flexible “oxy” linkage between the 4,4′-linked phenylene rings of H2L3 results in generation of a dinuclear [Cu2L2] species rather than a trinuclear (triangular) [Cu3L3] species of the type formed by the more rigid bis-β-diketonato ligand analogue in which the biphenylene rings separating the β-diketone domains are directly coupled in their 4,4′ positions. [ABSTRACT FROM AUTHOR]

Bis(N,N′-2,6-diisopropylphenyl)-6-aminofulvene-2-aldimine (4) has been synthesised and characterised. The synthesis and characterisation of two zwitterionic Pd(ii) complexes [(Ph2AFA)Pd(Me)DMAP] (1) and [(Ph2AFA)Pd(N,N-dimethylbenzylamine-2-C,N)] (2) are reported. Activation of 1and 2for ethene polymerisation with Lewis acids such as BF3and B(C6F5)3were not successful. Attempted synthesis of halide-bridged dimers of the form [(Ph2AFA)Pd(μ-X)]2resulted in formation of bis-chelated complexes [(Cy2AFA)2Pd] (3) and [(tBu2AFA)2Pd] (5). [ABSTRACT FROM AUTHOR]

Protonated amidopyridyl ligands show high selectivity for the extraction of [CoCl4]2+ or [ZnCl4]2+ over chloride ion into organic media via the formation of N-H and C-H hydrogenbond donors to the outer coordination spheres of the chlorometallates. [ABSTRACT FROM AUTHOR]

Three novel materials ( 5CzICz , Cz 2 ICz and Cz 3 ICz ), based on the indolo[3,2,1- jk ]carbazole and 9 H -carbazole building blocks, with high triplet energies ( E T > 2.80 eV) and good thermal stability ( T g > 101 °C) were synthesized, characterized and applied as host materials in PhOLED devices. In course of the preparation of the materials, an improved protocol for the synthesis of the indolo[3,2,1- jk ]carbazole moiety has been developed. The careful molecular design of the title compounds allowed to avoid excimer formation of the indolo[3,2,1- jk ]carbazole subunits in thin films. Therefore, the improved molecular design broadened the applicability of indolo[3,2,1- jk ]carbazole host materials and significantly enhanced the efficiency of PhOLED devices based on these derivatives compared to previously reported indolo[3,2,1- jk ]carbazole based compounds. Accordingly, employing the newly developed materials red (CE max : 32.7 cd A -1 , PE max : 31.0 lm W -1 , EQE max : 20.4%), green (CE max : 81.0 cd A -1 , PE max : 87.4 lm W -1 , EQE max : 21.5%) and blue (CE max : 35.5 cd A -1 , PE max : 39.9 lm W -1 , EQE max : 18.0%) PhOLED devices with a remarkably low efficiency roll-off at 1000 cd m -2 ( Cz 2 ICz - red: 5%; green: 0%; blue: 6%) were fabricated.

The sequential interaction of preformed [Cu2(L1)2(THF)2] (where H2L1 is 1,1-(1,3-phenylene)-bis(4,4-dimethylpentane-1,3-dione incorporating a 1,3-phenylene linker between its two β-diketone domains) and [Cu2(L4)2]·2H2O (where H2L4 is 1,1-(4,4′-oxybiphenylene)-bis(4,4-dimethylpentane-1,3-dione) incorporating a flexible oxybiphenylene linkage between the two β-diketone groups) with the potentially difunctional aliphatic non-planar co-ligands, N-methylpiperazine (mpip), N,N′-dimethylpiperazine (dmpip) and 1,4-thiomorpholine (thiomorph) is reported. A series of extended molecular assemblies exhibiting a range of di- and tetranuclear assemblies were obtained and their X-ray structures determined. Dinuclear [Cu2(L1)2(mpip)2]·2mpip incorporates two 5-coordinate, square pyramidal metal centres as does tetranuclear [{Cu2(L1)2}2(dmpip)2]·2dmpip. In contrast, dinuclear [Cu2(L1)2(dmpip)4]·dmpip and [{Cu2(L1)2}2(thiomorph)4]·3thiomorph each contain two 5-coordinate and two 6-coordinate centres. Each of [Cu2(L4)2(THF)2]·2THF and Cu2(L4)2(mpip)2]·H2O incorporate only 5-coordinate metal centres, with the latter complex forming a one-dimensional hydrogen bonded ribbon-like structure directed along the crystallographic a-axis. In keeping with the documented tendency for the smallest, least strained assembly to form in supramolecular self-assembly processes, the incorporation of the flexible “oxy” linkage between the 4,4′-linked phenylene rings of H2L3 results in generation of a dinuclear [Cu2L2] species rather than a trinuclear (triangular) [Cu3L3] species of the type formed by the more rigid bis-β-diketonato ligand analogue in which the biphenylene rings separating the β-diketone domains are directly coupled in their 4,4′ positions.

In this work UVA and blue light have been used to study photo-isomerisation about the C=C double bond in complexes of the type [PtCl(-CH=CHAr)(tmeda)] [Ar = C6H5, (E)-2a; 4-CH3O-C6H4, (E)-2b; 3-NO2-C6H4, (E)-2c; and 3-CH3O-C6H4, (E)-2d]. The progress of the reaction has been monitored by NMR spectroscopy following irradiation of the NMR sample. The NMR data have been complemented with X-ray diffractometric analysis of compounds (E)-2a-c and (Z)-2a. The kinetic data clearly indicate that a monomolecular mechanism is operating with the energy of the irradiating light influencing the rate of isomerisation but not the equilibrium composition, which is only slightly in favour of the Z isomer. DFT and TD-DFT theoretical investigations have been carried out to elucidate the nature of the main electronic transitions in the UV-Vis region and the mechanism of the photo-isomerisation reaction appears to proceed through a C=C bond twist process similar to that involved in purely organic molecules such as stilbene. In the Z isomer, one ortho proton of the phenyl group can come close to platinum (Pt···H(ortho) distance of 2.632 Å in (Z)-2a). In the case of 2c, the difference in chemical shift between the two ortho protons varies from 3.30 ppm in the Z isomer, where interaction with Pt is possible, to 0.60 ppm in the E isomer, where such interaction cannot take place. The analysis of the DFT orbitals indicates that the most shifted H(ortho) is that with a greater positive charge, pointing to an H-bond type of interaction.

A simple and convenient route to η(5)-coordinated Ru and Rh aminofulvene-aldiminate (AFA) complexes is described. The metalloligands [Cp*Ru{η(5)-(Ph(2)AFAH)}][BF(4)] (3), [Cp*Ru{η(5)-(benzyl(2)AFAH)}][OTf] (7), [Cp*Rh{η(5)-(Cy(2)AFA)H}][BF(4)](2) (8) and [Cp*Rh{η(5)-(Cy(2)AFA)}][BF(4)] (9) have been synthesised and characterised. The basicity of 9 has been found to be significantly less than its neutral analogue and thus eliminates the need for a deprotonation step to ligate to a second metal in the κ(2)-N,N'-coordination mode. The reaction of 9 with a palladium precursor provides a mixed-metal complex [Cp*Rh(η(5)/κ(2)-Cy(2)AFA)PdCl(2)][BF(4)] (12). Cyclic voltammetry studies of the Ph(2)AFAH ligand shows an irreversible one electron oxidation peak at +1.0 V (vs. Fc/Fc(+)). Complex 3 shows an irreversible oxidation at +1.5 V and a reduction peak at -1.0 V. The oxidation of 3 occurs on the AFA ligand backbone whereas the structurally analogous neutral 1,2-bis(imidoyl)pentamethyl-ruthenocene shows reversible oxidation at the Ru center.

A tripodal iminopyrrole provides an environment suited to the encapsulation of water through hydrogen-bonding, and the formation of metal complexes by deprotonation and imine-pyrrole tautomerisation., (© The Royal Society of Chemistry 2011)

A cobalt aquo-hydroxo complex of a ditopic Schiff-base pyrrole-crown ether macrocycle has been prepared and forms a rigid Pacman-clefted structure that assembles through hydrogen-bonding into a hexagonal wheel motif in the solid state.

The syntheses, structures and magnetic properties of six iron complexes stabilised with the derivatised salicylaldoxime ligands Me-saoH(2) (2-hydroxyethanone oxime) and Et-saoH(2) (2-hydroxypropiophenone oxime) are discussed. The four hexanuclear and two octanuclear complexes of formulae [Fe(8)O(2)(OMe)(4)(Me-sao)(6)Br(4)(py)(4)]·2Et(2)O·MeOH (1·2Et(2)O·MeOH), [Fe(8)O(2)(OMe)(3.85)(N(3))(4.15)(Me-sao)(6)(py)(2)] (2), [Fe(6)O(2)(O(2)CPh-4-NO(2))(4)(Me-sao)(2)(OMe)(4)Cl(2)(py)(2)] (3), [Fe(6)O(2)(O(2)CPh-4-NO(2))(4)(Et-sao)(2)(OMe)(4)Cl(2)(py)(2)]·2Et(2)O·MeOH (4·2Et(2)O·MeOH), [HNEt(3)](2)[Fe(6)O(2)(Me-sao)(4)(SO(4))(2)(OMe)(4)(MeOH)(2)] (5) and [HNEt(3)](2)[Fe(6)O(2)(Et-sao)(4)(SO(4))(2)(OMe)(4)(MeOH)(2)] (6) all are built from a series of edge-sharing [Fe(4)(μ(4)-O)](10+) tetrahedra. Complexes 1 and 2 display a new μ(4)-coordination mode of the oxime ligand and join a small group of Fe-phenolic oxime complexes with nuclearity greater than six.

New examples of nitrogen base adducts of dinuclear Co(II), Ni(II) and Cu(II) complexes of the doubly deprotonated forms of 1,3-aryl linked bis-beta-diketones of type [RC(=O)CH(2)C(=O)C(6)H(4)C(=O)CH(2)C(=O)R] (L(1)H(2)) incorporating the mono- and difunctional amine bases pyridine (Py), 4-ethylpyridine (EtPy), piperidine (pipi), 1,4-piperazine (pip), N-methylmorpholine (mmorph), 1,4-dimethylpiperazine (dmpip) and N,N,N',N'-tetramethylethylenediamine (tmen) have been synthesised by reaction of the previously reported [Cu(2)(L(1))(2)].2.5THF (R = Me), [Cu(2)(L(1))(2)(THF)(2)] (R = t-Bu), [Ni(2)(L(1))(2)(Py)(4)] (R = t-Bu) and [Co(2)(L(1))(2)(Py)(4)] (R = t-Bu) complexes with individual bases of the above type. Comparative X-ray structural studies involving all ten base adduct derivatives have been obtained and reveal a range of interesting discrete and polymeric molecular architectures. The respective products have the following stoichiometries: [Cu(2)(L(1))(2)(Py)(2)].Py (R = Me), [Cu(2)(L(1))(2)(EtPy)(2)].2EtPy (R = t-Bu), [Cu(2)(L(1))(2)(pipi)(2)].2pipi (R = t-Bu), [Cu(2)(L(1))(2)(mmorph)(2)] (R = t-Bu), [Cu(2)(L(1))(2)(tmen)(2)] (R = t-Bu) and {[Cu(2)(L(1))(2)(pip)].pip.2THF}(n), [Co(2)(L(1))(2)(tmen)(2)] (R = t-Bu), [Ni(2)(L(1))(2)(Py)(4)].dmpip (R = t-Bu), [Ni(2)(L(1))(2)(pipi)(4)].pipi (R = t-Bu) and [Ni(2)(L(1))(2)(tmen)(2)] (R = t-Bu). The effect of pressure on the X-ray structure of [Cu(2)(L(1))(2)(mmorph)(2)] has been investigated. An increase in pressure from ambient to 9.1 kbar resulted in modest changes to the unit cell parameters as well as a corresponding decrease of 6.7 percent in the unit cell volume. While a small 'shearing' motion occurs between adjacent molecular units throughout the lattice, no existing bonds are broken or new bonds formed.

The syntheses, structures and magnetic properties of nine new iron complexes containing salicylaldoxime (saoH(2)) or derivatised salicylaldoximes (R-saoH(2)), [Fe(3)O(OMe)(Ph-sao)(2)Cl(2)(py)(3)].2MeOH (1.2MeOH), [Fe(3)O(OMe)(Ph-sao)(2)Br(2)(py)(3)].Et(2)O (2.Et(2)O), [Fe(4)(Ph-sao)(4)F(4)(py)(4)].1.5MeOH (3.1.5MeOH), [Fe(6)O(2)(OH)(2)(Et-sao)(2)(Et-saoH)(2)(O(2)CPh)(6)] (4), [HNEt(3)](2)[Fe(6)O(2)(OH)(2)(Et-sao)(4)(O(2)CPh(Me)(2))(6)].2MeCN (5.2MeCN), [Fe(6)O(2)(O(2)CPh)(10)(3-(t)But-5-NO(2)-sao)(2)(H(2)O)(2)].2MeCN (6.2MeCN), [Fe(6)O(2)(O(2)CCH(2)Ph)(10)(3-(t)But-sao)(2)(H(2)O)(2)].5MeCN (7.5MeCN), {[Fe(6)Na(3)O(OH)(4)(Me-sao)(6)(OMe)(3)(H(2)O)(3)(MeOH)(6)].MeOH}n (8.MeOH) and [HNEt(3)](2)[Fe(12)Na(4)O(2)(OH)(8)(sao)(12)(OMe)(6)(MeOH)(10)] (9) are discussed. The predominant building block appears to be the triangular [Fe(3)O(R-sao)(3)](+) species which can self-assemble into more elaborate arrays depending on reaction conditions. An interesting observation is that the R-saoH(-)/R-sao(2-) ligand system tends to adopt coordination modes similar to carboxylates. The most unusual molecule is the [Fe(4)F(4)] molecular square, 3. While Cl(-) and Br(-) appear to act only as terminal ligands, the F(-) ions bridge making a telling impact on molecular structure and topology.

3-Dialkylaminomethyl substituted salicylaldoximes are efficient metal salt extractants, and, in contrast to related "salen"-based reagents, are sufficiently stable to acid hydrolysis to allow commercial application in base metal recovery. Crystal structures show that metal salts are bound by a zwitterionic form of the reagents, with copper(II) nitrate, tetrafluoroborate and trifluoroacetate forming [Cu()(2)X(2)] assemblies in a tritopic arrangement with a trans-disposition of the anions outwith the coordination sphere. Copper(II) chloride, bromide and zinc(II) chloride form 1:1 assemblies, [Cu()X(2)], with the halides in the inner coordination sphere of the metal, leading to high chloride selectivity and very good mass transport efficiencies of CuCl(2). Introduction of the anion-binding sites into the salicylaldoxime extractants changes their cation selectivities; the ligands co-extract small amounts of Fe(III) along with Cu(II) from mixed metal aqueous feed solutions, an issue which will need to be addressed prior to industrial application.

Bis(N,N'-2,6-diisopropylphenyl)-6-aminofulvene-2-aldimine (4) has been synthesised and characterised. The synthesis and characterisation of two zwitterionic Pd(ii) complexes [(Ph(2)AFA)Pd(Me)DMAP] (1) and [(Ph(2)AFA)Pd(N,N-dimethylbenzylamine-2-C,N)] (2) are reported. Activation of 1 and 2 for ethene polymerisation with Lewis acids such as BF(3) and B(C(6)F(5))(3) were not successful. Attempted synthesis of halide-bridged dimers of the form [(Ph(2)AFA)Pd(mu-X)](2) resulted in formation of bis-chelated complexes [(Cy(2)AFA)(2)Pd] (3) and [((t)Bu(2)AFA)(2)Pd] (5).

Uptake of a tetrafluoroborate anion into the centre of a dicopper bis-salicylaldoxime complex causes a major contraction of the cavity and an increase in helicity.

Novel polynucleating, di- and tri-acidic ligands have been designed to increase the molar and mass transport efficiencies for the recovery of base metals by solvent extraction.

Benzohydroxamic acid is shown to be an unexpectedly good ligand for iron(iii) oxides, favouring surface attachment to the formation of trisbenzohydroxamato complexes, which are known to have very high thermodynamic stability in solution.

Attaching dialkylaminomethyl arms to commercial phenolic oxime copper extractants yields reagents which transport base metal salts very efficiently by forming neutral 1:1 or 1:2 complexes with zwitterionic forms of the ligands.

The synthesis and magnetic properties of the compounds [HNEt(3)][Fe(2)(OMe)(Ph-sao)(2) (Ph-saoH)(2)].5MeOH (1.5MeOH), [Fe(3)O(Et-sao)(O(2)CPh)(5)(MeOH)(2)].3MeOH (2.3MeOH), [Fe(4)(Me-sao)(4)(Me-saoH)(4)] (3), [HNEt(3)](2)[Fe(6)O(2)(Me-sao)(4)(SO(4))(2)(OMe)(4)(MeOH)(2)] (4), [Fe(8)O(3)(Me-sao)(3)(tea)(teaH)(3)(O(2)CMe)(3)] (5), [Fe(8)O(3)(Et-sao)(3)(tea)(teaH)(3)(O(2)CMe)(3)] (6), and [Fe(8)O(3)(Ph-sao)(3)(tea)(teaH)(3)(O(2)CMe)(3)] (7) are reported (Me-saoH(2) is 2'-hydroxyacetophenone oxime, Et-saoH(2) is 2'-hydroxypropiophenone oxime and Ph-saoH(2) is 2-hydroxybenzophenone oxime). 1-7 are the first Fe(III) compounds synthesised using the derivatised salicylaldoxime ligands, R-saoH(2). 1 is prepared by treatment of Fe(2)(SO(4))(3).6H(2)O with Ph-saoH(2) in the presence of NEt(3) in MeOH; 2 prepared by treatment of Fe(ClO(4))(2).6H(2)O with Et-saoH(2) and NaO(2)CPh in the presence of NEt(4)OH in MeOH; 3 prepared by treatment of Fe(ClO(4))(2).6H(2)O with Me-saoH(2) and NaO(2)CCMe(3) in the presence of NEt(4)OH in MeOH; and 4 prepared by treatment of Fe(2)(SO(4))(3).6H(2)O with Me-saoH(2) in the presence of NEt(3) in MeOH. 4 is a rare example of a polynuclear iron complex containing a coordinated SO(4)(2-) ion. Compounds 5-7 are prepared by treatment of Fe(O(2)CMe)(2) with Me-saoH(2) (5), Et-saoH(2) (6), Ph-saoH(2) (7) in the presence of H(3)tea (triethanolamine) in MeOH, and represent the largest nuclearity Fe(III) clusters containing salicyladoxime-based ligands, joining a surprisingly small family of characterised octanuclear Fe complexes. Variable temperature magnetic susceptibilty measurements of 1, 3 and 5-7 reveal all five complexes possess S = 0 spin ground states; 2 possesses an S = 1/2 spin ground state, while 4 has an S = 4 +/- 1 spin ground state.