Change search
Refine search result
1 - 32 of 32
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 1. Banyai, I.
    et al.
    Glaser, Julius
    KTH, Superseded Departments, Chemistry.
    Toth, I.
    Cyanide exchange on Tl(CN)(4)(-) in aqueous solution studied by Tl-205 and C-13 NMR spectroscopy2001In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 7, p. 1709-1717Article in journal (Refereed)
    Abstract [en]

    Dynamics of cyanide exchange between Tl((CN)-C-13)(4)(-) and (CN-)-C-13 was studied by means Tl-205 and C-13 NMR. The rate law consists of two parts: w = k(CN)[Tl(CN)(4)(-)][CN-] + k(OH)[Tl(CN)(4)(-)][CN-][OH-] with k(CN) = 9.7(+/-0.4) x 10(6) M(-1)s(-1) and k(OH) = 5.4(+/-0.4) x 10(10) M(-2)s(-1). It was shown that the exchange between the two cyano species can be studied, not only by C-13 NMR, but also by Tl-205 NMR using the heteronuclear carbon-thallium scalar coupling as an indicator, despite the fact that only one Tl site is present in the system. The reaction mechanism is discussed in terms of an associative interchange mechanism, I-A. Penetration of the incoming cyanide ion into the coordination sphere of Tl(CN)(4)(-) Tl(CN)(4)(OH)(-) is suggested to be the rate-determining step for the two parallel reactions paths. Possible reasons for the strong labilizing effect of the cyanide ligand is discussed in the light of thermodynamic and structural data. The possibility of detection of an exceptional exchange reaction, namely cyanide exchange between two Tl(CN)(4)(-) entities by a direct encounter was theoretically settled, but found to be too slow to be detected.

  • 2. Berg, K. E.
    et al.
    Tran, A.
    Raymond, M. K.
    Abrahamsson, M.
    Wolny, J.
    Redon, S.
    Andersson, M.
    Sun, Licheng C.
    Styring, S.
    Hammarstrom, L.
    Toftlund, H.
    Akermark, B.
    Covalently linked ruthenium(II)-manganese(II) complexes: Distance dependence of quenching and electron transfer2001In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 4, p. 1019-1029Article in journal (Refereed)
    Abstract [en]

    Continuing our development of artificial models for photosystem II in green plants, a series of compounds have been prepared in which a RU(bpy)(3)(2+) photosensitizer is covalently Linked to a manganese(II) electron donor. In addition to a trispicolylamine Ligand, two other manganese Ligands, dipicolylamine and aminodiacetic acid, have been introduced in order to study Ligands that are appropriate for the construction of manganese dimers with open coordination sites for the binding of water. Coordination equilibria of the manganese ions were monitored by EPR. The interactions between the ruthenium and manganese moieties were probed by flash photolysis, cyclic voltammetry and steady-state and time-resolved emission measurements. The quenching of the Ru-II excited state by Mn-II was found to be rapid in complexes with short Ru-Mn distances. Nevertheless, each Run species could be photo-oxidized by bimolecular quenching with methylviologen, and the subsequent electron transfer from Mn-II to Ru-III could be monitored.

  • 3.
    Durieux, Guillaume
    et al.
    CNRS, Ecole Normale Super, Dept Chim.
    Gerdin, Martin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Moberg, Christina
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Jutand, Anny
    CNRS, Ecole Normale Super, Dept Chim.
    Rate and Mechanism of the Oxidative Addition of a Silylborane to Pt0 Complexes: Mechanism for the Pt-Catalyzed Silaboration of 1,3-Cyclohexadiene2008In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 27, p. 4236-4241Article in journal (Refereed)
    Abstract [en]

    The chemical reduction of Pt(acac)(2) by DIBALH in the presence of phosphanes, which is used to generate active Pt-0 complexes in the Pt-catalyzed silaboration of cyclohexadiene by 2-(diinethylphenylsilyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1) leading to the 1,4-silaborated product, was mimicked by the electrochemical reduction of Pt(acac)(2) in the presence of 2 equiv. of PR3 (R = Ph, nBu). The electrochemical reduction generates free acac anions and neutral Pt-0-(PR3)(2) complexes. The kinetics of the oxidative addition of bromobenzene (used first as a model molecule) and silylborane 1 to the Pt-0 complexes was investigated and the rate constants determined. Pt-0(PnBu(3))(2) is much more reactive than Pt-0(PPh3)(2) towards 1. From the electrochemical study, it emerges that the acac anions released in the reduction of Pt(acac)(2) do not coordinate to the Pt-0(PR3)(2) complexes. Consequently, the rate of the oxidative addition of 1 to Pt-0(PR3)(2), generated either by the electrochemical reduction or by the chemical reduction by DIBALH, is not affected by the acac anions and a posteriori not by aluminum cations. The oxidative addition and the further step of the catalytic cycle [insertion of the diene into the Pt-B bond of the Si-Pt-B complex generated in the oxidative addition, with formation of the eta(3)-allyl)Pt-Si complex] were monitored by NMR spectroscopy. Pt-0 and Pt-II complexes involved in the catalytic cycle were characterized. The oxidative addition is faster when the ligand is PMe2Ph relative to that obtained with PPh3, in agreement with the electrochemical data. No reductive elimination within the ((eta(3)-allyl))Pt-Si complex is observed when the ligand is PMe2Ph, whereas reactions in the presence of PPh3 proceeded to give the final product. As a consequence, PPh3 is a better ligand than PMe2Ph for the catalytic reaction, as observed experimentally.

  • 4. Forcato, M.
    et al.
    Lake, F.
    Blazquez, M. M.
    Renner, P.
    Crisma, M.
    Gade, L. H.
    Licini, G.
    Moberg, Christina
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Chiral, enantiopure aluminum(III) and titanium(IV) azatranes2006In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 5, p. 1032-1040Article in journal (Refereed)
    Abstract [en]

    Al-III and Ti-IV complexes of C-3-symmetric tetradentate trisamidoamme ligands with trigonal bipyramidal coordination geometry, containing chlorine or dialkylamido groups, or with a free coordination site in the apical position, have been synthesised by salt metathesis and amine elimination. Products with threefold symmetry were generally obtained for tetravalent titanium, whereas for the aluminium complexes either asymmetric structures with two of the three podand arms taking part in coordination to the metal or symmetric arrangements possessing the full threefold symmetry were formed depending on the steric properties of the ligands.

  • 5. Gao, Weiming
    et al.
    Sun, Junliang
    Li, Mingrun
    Akermark, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Romare, Kristina
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Åkermark, Björn
    Synthesis of a [3Fe2S] Cluster with Low Redox Potential from [2Fe2S] Hydrogenase Models: Electrochemical and Photochemical Generation of Hydrogen2011In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 7, p. 1100-1105Article in journal (Refereed)
    Abstract [en]

    In the attempted replacement of carbon monoxide by the bis(phosphane) dppv in a dinuclear [2Fe2S] complex, a trinuclear [3Fe2S] complex with two bis(phosphane) ligands was unexpectedly obtained. On protonation, this gave a bridged hydride complex with an unusually low potential for the reduction of protons to molecular hydrogen. The redox potential also appears sufficiently positive for direct electron transfer from an excited [Ru(bpy)(3)](2+) sensitizer.

  • 6.
    Gorlov, Mikhail
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Hussami, Linda
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Fischer, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Kloo, Lars A.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Mononuclear eta(6)-Arene Complexes of Lanthanides: One-Step Syntheses, Crystal Structures, and Arene Exchange2008In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 33, p. 5191-5195Article in journal (Refereed)
    Abstract [en]

    Gallium(III) halides react with cerium(III), ytterbium(III), or dysprosium(III) halides in the presence of alkylated benzenes yielding mononuclear complexes of the general formula [Ln(eta(6)-arene)(GaX4)(3)]. The X-ray structures of [Ce(C6H5Me)- (GaCl4)(3)] (1), [Ce(p-C6H4Me2)(GaCl4)(3)]center dot 0.5(p-C6H4Me2) (2), [Yb(C6H5Me)(GaCl4)(3)] (3), [Yb(p-C6H4Me2)(GaCl4)(3)]center dot 0.5(p- C6H4Me2) (4), and [Dy(C6H5Me)(GaBr4)(3)] (5) were determined. Arene ligands in the cerium-toluene compound 1 can be substituted by polycyclic aromatic hydrocarbons (PAHs); the compounds [Ce(naphthalene) (GaCl4)(3)] (6) and [Ce(pyrene)(GaCl4)(3)]center dot 0.5(pyrene) (7) have been isolated and structurally characterized.

  • 7. Hetterscheid, D. G. H.
    et al.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Water oxidation2014In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 4, p. 571-572Article in journal (Refereed)
  • 8.
    Hopmann, Kathrin H.
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Himo, Fahmi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    On the Role of Tyrosine as Catalytic Base in Nitrile Hydratase2008In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 22, p. 3452-3459Article in journal (Refereed)
    Abstract [en]

    Nitrile Hydratases (NHases) catalyze the conversion of nitriles to their corresponding amides. Two NHase classes exist, the Fe-III-NHases and the Co-III-NHases. Both harbour an intriguing active site, with a low-spin metal ion coordinated to deprotonated back-bone amides and oxidized cysteine residues. So far it has not been possible to conclusively determine the reaction mechanism of NHase. Here we employ density functional theory to investigate the recent proposal that a fully conserved second-shell tyrosine residue is the catalytic base of nitrile hydratase (J. Biol. Chem. 2007, 282, 7397-7404). In the proposed mechanism, the tyrosine is suggested to be in the tyrosinate state and to mediate nitrile hydration through activation of a water molecule, which attacks the metal-bound substrate. We have explored this mechanism employing quantum chemical active site models on the basis of the Co-III-NHase from P. thermophila JCM 3095 and the Fe-III-NHase from R. erythropolis N-771. Potential energy curves and optimized transition states are presented. The computed barriers for the two models are a few kcal/mol above the experimental value, indicating that the conserved second-shell tyrosine could function as the catalytic base of NHase. To further evaluate the likelihood of this mechanism, we estimated the pK(a) value of the second-shell tyrosine in each model. We also provide estimates of the energy involved in the exchange of a metal-bound water molecule with a nitrile substrate.

  • 9.
    Hopmann, Kathrin H.
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Himo, Fahmi
    KTH, School of Biotechnology (BIO), Theoretical Chemistry.
    Theoretical Investigation of the Second-Shell Mechanism of Nitrile Hydratase2008In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 9, p. 1406-1412Article in journal (Refereed)
    Abstract [en]

    Nitrile hydratases (NHases) are biocatalytically important enzymes that are utilized in the industrial production of acrylamide and nicotinamide. There are two different classes of NHases, harbouring either a low-spin Fe-III or a low-spin Co-III ion in the active site, in each case with the same peculiar set of ligands, involving deprotonated backbone amides and oxidized cysteine residues. The detailed reaction mechanism of NHase has not been established yet, but different proposals have been put forward. Depending on the binding site of the substrate, these can be divided into first-shell and second-shell mechanisms, respectively, Recently, we have investigated different first-shell mechanisms using quantum-chemical active-site models based on the iron-dependent NHase (Inorg. Chem. 2007, 46, 4850). Here we continue our investigation of the NHase reaction by exploring two different variations of the second-shell mechanism of the iron-dependent NHase. In the first, a metal-bound hydroxide ion performs a nucleophilic attack on the nitrile substrate, while in the second investigated mechanism, the oxidized cysteine, Cys114-SO-, acts as the nucleophile. We report energies, optimized transition state, and intermediate geometries for both investigated mechanisms. The calculated barriers are similar to the previously reported first-shell mechanism involving Cys114-SO- as catalytic base.

  • 10. Huang, D. G.
    et al.
    Wang, W. G.
    Zhang, X. F.
    Chen, C. N.
    Chen, F.
    Liu, Q. T.
    Liao, D. Z.
    Li, L. C.
    Sun, Licheng C.
    Synthesis, structural characterizations and magnetic properties of a series of mono-, di- and polynuclear manganese pyridinecarboxylate compounds2004In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 7, p. 1454-1464Article in journal (Refereed)
    Abstract [en]

    Seven new manganese(II, III, IV) pyridinecarboxylate compounds (Et4N)[MnCl2(pic)(2)] (1, Hpic = picolinic acid) [MnCl(Pic)(2)(H2O)].H2O (2), [MnCl(pic)(H2O)2](n) (3), [Mn(Pic)(2)](n) (4), [MnCl(pic)](n) (5), [MnCl2(4-C5H4NHCOO)](n) (6) and [Mn2O2(pic)(4)] (7) were synthesized and structurally characterized. The picolinate ligand coordinates to the Mn ion forming a chelating five-membered ring which constructs diverse architectures by various bridging modes, such as mu-Cl, mu(1,1)(-) and mu(1,3)-carboxylate bridges (syn-syn and syn-anti modes). The interaction between the pyridyl rings is discussed, displaying a face-to-face pi-pi stacking for complex 6 and a T-shaped C-H...pi attraction for complex 4. Complex 3 has an infinite zigzag chain structure in which two neighboring Mn ions are linked by a carboxylate bridge in a syn-anti mode. In complex 4, the Mn(pic)(2) fragments are joined to each other by double mu(1,1)-carboxylate bridges, forming a 2D layer structure. Complex 5 contains Mn4O4 square subunits which are connected by double mu-Cl bridges to form a grid-like 2D structure. The isonicotinate complex 6 has a zigzag chain structure containing mixed double mu-Cl and mu(1,3)-carboxylate bridges in a syn-syn mode. Protonation at the pyridyl-N position was found and identified by the IR and magnetic properties of 6. The participation of an oxidizing agent like MnO4- leads to complexes containing higher valent manganese (1, 2 and 7). The IR spectra of these complexes are discussed and found to be consistent with the structural features. The magnetic properties of complexes 4, 5 and 6 have been investigated. Antiferromagnetic coupling interactions were observed and satisfactory fitting results were obtained with J values ranging from -0.63 cm(-1) to -2.35 cm(-1). The magnetic parameters of these complexes, together with the parameters of other Mn complexes with comparable structures, are compared and discussed based on the bridging modes. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).

  • 11. Huang, Yong
    et al.
    Gao, Weiming
    Åkermark, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Li, Mingrun
    Akermark, Bjorn
    An Air-Stable Fe3S4 Complex with Properties Similar to Those of the HOXair State of the Diiron Hydrogenases2012In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 27, p. 4259-4263Article in journal (Refereed)
    Abstract [en]

    A Fe3S4 complex bridged by azapropanedithiolate (adt), complex 6, was prepared as a potential model of the HOXair state of [FeFe]-hydrogenases. Complex 6 was characterized by IR and 1H NMR spectroscopy, and its structure was determined by X-ray crystallography. The electrochemical studies show that complex 6 is redox-active under acidic conditions, which provides insight into the catalytic mechanism. Hydrogen evolution, driven by visible light, was observed in CH3CN/D2O solution by online mass spectroscopy.

  • 12.
    Kloo, Lars
    et al.
    KTH, Superseded Departments, Chemistry.
    Rosdahl, Jan
    KTH, Superseded Departments, Chemistry.
    Svensson, Per H.
    KTH, Superseded Departments, Chemistry.
    On the Intra- and Intermolecular Bonding in Polyiodides2002In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 5, p. 1203-1209Article in journal (Refereed)
    Abstract [en]

    The nature of intra- and intermolecular interactions of poly-iodides has been investigated by means of quantum chemical methods and structural statistical data. In the region of "secondary bonds" the interaction is adequately described in terms of covalent bonding accompanied by dispersion. At greater distances the interaction is dominated by ion-quadrupole interactions between ionic and neutral iodine building blocks of the polyiodide structures.

  • 13. Kuznetsov, Alexei N.
    et al.
    Popovkin, Boris A.
    Ståhl, Kenny
    Lindsjö, Martin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Synthesis of main group polycations in molten and pseudo-molten GaBr3 media2005In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 24, p. 4907-4913Article in journal (Refereed)
    Abstract [en]

     The prospects of synthesizing polycationic species using GaBr3 in benzene solution at room temperature have been investigated. The salts Bi-8[GaBr4](2), Sb-8[GaBr4](2) and Te-4- [Ga2Br7](2) have been isolated and characterized. The first two compounds are isotypic with Sb-8[GaCl4](2), crystallize in the space group Pna2(1), and feature square anti-prismatic E-8(2+) polycations (E = Sb, Bi). Unit-cell parameters for Bi-8[GaBr4](2) are a = 18.3014(10) angstrom, b = 10.3391(6) angstrom and c = 13.5763(7) angstrom, and for Sb-8[GaBr4](2); a = 18.096(2) angstrom, b = 10.1572(9) angstrom and c = 13.2168(10) angstrom. Te-4[Ga2Br7](2) crystallizes in the space group P2(1)/c with a = 10.1600(9) angstrom, b = 10.8314(9) angstrom, c = 13.8922(10) angstrom and beta = 99.182(7)degrees, and features a square-planar Te-4(2+) polycation. The compound Bi-5[GaBr4](3) has been synthesized from molten GaBr3 and characterized by using powder diffractometry in space group Fm-3c; a = 17.6263(8) angstrom. The structure model for this compound suggests the included Bi-5(3+) cations to be practically freely oriented within its cavities in the solid phase.

  • 14. Lee, Bao-Lin
    et al.
    Karkas, Markus D.
    Johnston, Eric V.
    Inge, Andrew K.
    Tran, Lien-Hoa
    Xu, Yunhua
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Hansson, Örjan
    Zou, Xiaodong
    Åkermark, Björn
    Synthesis and Characterization of Oligonuclear Ru, Co and Cu Oxidation Catalysts2010In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 34, p. 5462-5470Article in journal (Refereed)
    Abstract [en]

    In this work, we report the preparation and crystal structures of three new oligonuclear complexes, Ru-2(bbpmp)(mu-OAc)(3) (4), [Co-2(bbpmp)(mu-OAc)(mu-OMe)](PF6) (5), [Cu-4(Hbbpmp)(2)(mu-OAc)(H2O)(2)](OAc)(PF6)(2) (6) {H(3)bbpmp = 2,6-bis[(2-hydroxybenzyl)-(2-pyridylmethyl)aminomethyl]-4-methylphenol (3)}. The structures of the complexes were determined by single-crystal X-ray diffraction. The oxidation states of ruthenium, cobalt and copper in the complexes are +3, +3 and +2, respectively. In 4 and 5, Ru-III and Co-III are coordinated to four oxygen and two nitrogen atoms in an octahedral geometry, while in 6, Cu-II adopts both octahedral (CuN2O4) and square-pyramidal (CuN2O3) geometry. The potential of the three complexes as oxidation catalysts has been investigated.

  • 15. Li, P.
    et al.
    Wang, M.
    He, C. J.
    Li, G. H.
    Liu, X. Y.
    Chen, C. N.
    Akermark, B.
    Sun, Licheng C.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Influence of tertiary phosphanes on the coordination configurations and electrochemical properties of iron hydrogenase model complexes: Crystal structures of (mu-S2C3H6)Fe-2(CO)(6-n)L-n (L = PMe2Ph, n=1, 2; PPh3 P(OEt)(3), n=1)2005In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 12, p. 2506-2513Article in journal (Refereed)
    Abstract [en]

    A series of mono- and disubstituted diiron complexes [(mu-pdt)-Fe-2(CO)(5)L] [pdt = 1,3-propanedithiolato; L = PMe3 (2), PMe2Ph (3), PPh3 (4), P(OEt)(3) (5)] and [(mu-pdt)Fe-2(CO)(4)L-2] [L = PMe2Ph (6), PPh3 (7), P(OEt)3 (8)] were prepared as Fe-only hydrogenase-active-site models by controllable CO displacement of [(mu-pdt)Fe-2(CO)(6)] by tertiary phosphanes. The coordination configurations of 3-6 were characterized by X-ray crystallography. Disubstituted diiron complex 6 features an apical/apical coordination mode, instead of the typical transoid basal/basal configuration. The electrochemistry of 2-6 and 8 was studied by cyclic voltammetry to evaluate the effects of different tertiary phosphane ligands on the redox properties of the iron atoms of model complexes.

  • 16. Li, Ping
    et al.
    Wang, Mei
    He, Chengjiang
    Liu, Xiaoyang
    Jin, Kun
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Phosphane and phosphite unsymmetrically disubstituted diiron complexes related to the Fe-only hydrogenase active site2007In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 23, p. 3718-3727Article in journal (Refereed)
    Abstract [en]

    A series of unsymmetrically disubstituted diiron complexes [(mu-pdt){Fe(CO)(2)L-1]{Fe(CO)(2)L-2}] [pdt = 1,3-propanedithiolato; L-1 = PMe3, L-2 = PMe2Ph, 4; PPh3, 5; PCy3, 6; P(OEt)(3), 7; L-1= PMe2Ph, L-2 = PPh3, 8; P(OEt)(3), 9; L-1 = P(OEt)(3), L-2 = PPh3, 10; PCy3, 11] and [(mu-edt){Fe(CO)(2)PMe3)}{Fe(CO)(2)PPh3}] (edt = 1, 2-ethane dithiolato, 12) were prepared by means of step-wise CO displacements of [(mu-pdt)Fe-2(CO)(6)] and [(mu-edt)-Fe-2(CO)(6)] by different tertiary phosphane and phosphite ligands. The interconversion of the irondithiacyclohexane ring and the rotation of the [Fe(CO)(2)PR3] subunit were studied using by variable-temperature P-31{H-1} NMR spectroscopy of 4, 6 and 12 in solution. The molecular structures of 4-6, 8-10 and 12 show that complexes 4-6, 8, 9 and 12 possess an apical/basal coordination mode and complex 10 has an apical/apical conformation. The X-ray analyses indicate that the PMe2Ph ligand in the apical position of the starting complex [(mu-pdt){Fe(CO)(3)}{FeCO2(PMe2Ph)}] rotates to the basal position on conversion to the products 8 and 9. Cyclic voltammograms of 4-11 were studied both under argon and CO. The influences of the phosphane and phosphite ligands on the redox properties of the unsymmetrically disubstituted diiron complexes are discussed. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

  • 17. Liao, Rong-Zhen
    et al.
    Himo, Fahmi
    Yu, Jian-Guo
    Liu, Ruo-Zhuang
    Theoretical study of the RNA hydrolysis mechanism of the dinuclear zinc enzyme RNase Z2009In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 20, p. 2967-2972Article in journal (Refereed)
    Abstract [en]

     RNase Z is a dinuclear zinc enzyme that catalyzes the removal of the tRNA 3'-end trailer. Density functional theory is used to investigate the phosphodiester hydrolysis mechanism of this enzyme with a model of the active site constructed on the basis of the crystal structure. The calculations imply that the reaction proceeds through two steps. The first step is a nucleophihc attack by a bridging hydroxide coupled with protonation of the leaving group by a Glu-His diad. Subsequently, a water molecule activated by the same Glu-His diad makes a reverse attack, regenerating the bridging hydroxide. The second step is calculated to be the rate-limiting step with a barrier of 18 kcal/mol, in good agreement with experimental kinetic studies. Both zinc ions participate in substrate binding and orientation, facilitating nucleophilic attack. In addition, they act as electrophilic catalysts to stabilize the pentacoordinate trigonal-bipyramidal transition states.

  • 18. Lindsjo, Martin
    et al.
    Kloo, Lars A.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Kuznetzov, Alexei
    Popovkin, Boris
    Bi16I4 - A New Bismuth Subiodide: An Analysis of Molecular Packing and Electronic Structures of the Compounds in the BimI4 (m=14, 16, 18) Family2008In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 33, p. 5196-5202Article in journal (Refereed)
    Abstract [en]

    A new bismuth subiodide Bi16I4 was synthesized by hightemperature synthesis. Its structure was determined by single-crystal X-ray diffraction analysis [C2/m (No. 12), a = 25.948(6) angstrom, b = 4.354(1) angstrom, c = 13.259(3) angstrom, beta = 104.48(2)circle, Z = 2, R-1 = 0.041, wR(all)(F-2) = 0.109]. The compound belongs to the BimI4 (m = 14, 16, 18) family of low-dimensional subhalides that feature one-dimensional bismuth stripes of varying width, terminated by iodine atoms. Ab initio calculations at the I)FT level were performed on 31) structures of all three BimI4 compounds of the family. According to the computational data all three compounds are expected to exhibit metallic behavior and Pauli paramagnetism, with a directional anisotropy of the properties indicated by the calculated band structures. The molecular packing in bismuth subiodides has been analyzed in detail and two homologous series - Bi8+4nI4 and Bi10+4nI4 (n = 0, 1, 2, ...) - are suggested to describe existing and possible structures of the compounds of the BimI4 family. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

  • 19.
    Lindsjö, Martin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Fischer, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Improvements of and insights into the isolation of bismuth polycations from benzene solution - Single-crystal structure determinations of Bi-8[GaCl4](2) and Bi-5[GaCl4](3)2005In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, Vol. 2005, no 4, p. 670-675Article in journal (Refereed)
    Abstract [en]

    The synthesis, crystal growth and structure are reported for the two salts Bi-5[GaCl4](3) and Bi-8[GaCl4](2). The compounds are prepared from a solution of BiCl3 and GaCl3 in benzene, using gallium metal as reducing agent. Bi-8[GaCl4](2) contains a Bi-8(2+) polycation that, essentially, adopts an ideal square antiprismatic geometry. The compound crystallizes in the P6(3) space group; a = 17.760(2) Angstrom and c = 12.979(3) Angstrom. Bi-5[GaCl4](3) crystallizes in the R3c space group, a = 11.814(2) Angstrom, c = 29.974(3) Angstrom, and contains a Bi-5(3+) cation adopting a trigonalbipyramidal geometry. The cation is slightly distorted from the ideal D-3h symmetry.

  • 20. Lomoth, R.
    et al.
    Huang, P.
    Zheng, J. T.
    Sun, Licheng C.
    Hammarstrom, L.
    Akermark, B.
    Styring, S.
    Synthesis and characterization of a dinuclear manganese(III,III) complex with three phenolate ligands2002In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 11, p. 2965-2974Article in journal (Refereed)
    Abstract [en]

    A dinuclear manganese complex ([Mn2L(mu-OAc)(2)]PF6) has been synthesized, where L is the trianion of 2,6-bis{[(2-hydroxy-3,5-di- tert-butylbenzyl) (2-pyridylmethyl) amino] methyl)-4-methylphenol, a ligand with three phenolate groups. The two pseudo-octahedrally coordinated Mn ions are bridged via the two bidentate acetate ligands and the 4-methylphenolate group of the ligand. We have characterized the complex with electrochemistry, spectroelectrochemistry and EPR spectroscopy. Electrochemically the Mn-2(III,III) complex undergoes two metal-centered quasi-reversible one-electron reduction steps (E-1/2 = 0.04 and -0.32 V vs. SCE). Reduction to the Mn-2(II,III) state results in transformation into a modified complex with slightly different redox properties. One-electron oxidation (E-1/2 = 0.96 V vs. SCE) affords the Mn-2(III,IV) state while further one-electron oxidation (E-1/2 = 1.13 V vs. SCE) presumably involves ligand oxidation. High valent Mn complexes involving Mn-IV or Mn-V centers are of particular interest as intermediates in catalytic water oxidation. The redox potentials of [Mn2L(mu-OAC)(2)](+) show the expected stabilization of higher manganese oxidation states compared with the related complex, [Mn-2(bpmp)(mu-OAc)(2)](+).

  • 21. Ma, C. B.
    et al.
    Chen, C. N.
    Liu, Q. T.
    Chen, F.
    Liao, D. Z.
    Li, L. C.
    Sun, Licheng C.
    Great framework variation of polymers in the manganese(II) maleate/alpha,alpha' - Diimine system: Syntheses, structures, and magneto-structural correlation2003In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 15, p. 2872-2879Article in journal (Refereed)
    Abstract [en]

    Three novel manganese(II) coordination polymers, [Mn (maleate)(phen)](n) (1; phen = 1,10-phenanthroline), [Mn-(maleate)(phen)](n).nH(2)O (2), and [Mn(maleate)(bpy)](n) (3; bpy = 2,2'-bipyridine), have been synthesized by treatment of Mn2+ with maleic acid with participation of chelate diimine ligands, and have been identified by single-crystal, X-ray diffraction to have either one-dimensional (1D) zigzag chain structures (1 and 2) or a two-dimensional (2D) sinuous layer structure (3). Each maleate dianion coordinates to three Mn centers, in different bridging modes (syn-anti in 1 and 2, syn-syn and anti-anti in 3). These compounds represent an interesting example of structural topology variation from 1D to 2D mediated by chemically similar auxiliary chelate ligands. Variable-temperature magnetic susceptibility measurements show weak anti-ferromagnetic exchange interactions between the adjacent Mn-II ions, with J = -0.06 cm(-1) (2) and J = -1.3 cm(-1), zJ' = -0.27 cm(-1) (3). The differences in the magnitudes of these coupling interactions agree well with the nature of the carb oxylate-bridging coordination of maleate.

  • 22. Ma, G. B.
    et al.
    Kritikos, M.
    Glaser, Julius
    KTH, Superseded Departments, Chemistry.
    Small platinum-thallium clusters stabilized by ethylenediamine, (NC)(5)Pt-Tl(en)(n-1) (n=1-3) - Characterization in solution and in the solid state2001In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 5, p. 1311-1319Article in journal (Refereed)
    Abstract [en]

    Three neutral binuclear platinum-thallium compounds containing a direct and naked (unsupported by ligands) metal-metal bond have been prepared in dimethyl sulfoxide (DMSO). The compounds have the formula [(NC)(5)Pt-Tl(en)(n-1)] (n = 1-3, for compounds 1, 2 and 3, respectively) and were found to exist in solution by means of multinuclear NMR (Pt-195, Tl-205, C-13 and H-1) and Raman spectroscopy. The compounds exhibit very large single bond Pt-195-Tl-205 spin-spin coupling constants of 48-66 kHz. In addition, the solid state analogues of 1 and 3, [(NC)(5)Pt-Tl(DMSO)(4)](DMSO) and [(NC)(5)Pt-Tl(en)(2)]-(DMSO)(2), were synthesized and their structures determined by single crystal X-ray diffraction. The metal-metal bond lengths of Pt-Tl are 2.6131(4) Angstrom and 2.6348(5) Angstrom in compounds I and 3, respectively. Crystal data for compound 1: monoclinic, space group Cc (No. 9), Z = 4, a = 17.2367(14), b = 9.5560(11), c = 17.7941(15) Angstrom, beta = 100.551(10)9 V = 2881.4(5) Angstrom (3), T = 110(1) K; and for compound 3: monoclinic, space group P2(1) (No. 4), Z = 2, a 9.3167(14), b 12.3007(13), c = 11.4586(16) Angstrom, beta = 112.318(16)degrees, V =1214.8(3) Angstrom (3), T = 110(1) K.

  • 23. Ma, G.
    et al.
    Fischer, Andreas
    KTH, Superseded Departments, Chemistry.
    Glaser, Julius
    KTH, Superseded Departments, Chemistry.
    Synthesis and structure of monomeric and platinum-bonded (1,10-phenanthroline)thallium complexes2002In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 6, p. 1307-1314Article in journal (Refereed)
    Abstract [en]

    Oxidative addition of (1,10-phenanthroline)thallium(III) complexes [TI(phen)(n)(solv)](3+) (n = 1-2) (phen = 1,10-phenanthroline) to [Pt(CN)(4)](2-) in DMSO, in the presence of cyanide ions and in the absence of cyanide ions yielded heterodinuclear metal-metal-bonded complexes, [(NC)(5)Pt-Tl(phen)(n)(solv)] and [(NC)(4)Pt-Tl(phen)(n)(solv)](+) (n = 0, 1, and 2), respectively, The presence of a direct Pt-Tl bond in the complex is evident by a very strong one-bond Pt-195-Tl-205 spin-spin coupling detected by Tl-205 NMR: (1)J = 94.0 kHz (1a), 84.2 kHz (2a), and 77.1 kHz (3a) corresponding to n 0, 1, and 2 in [(NC)(4)Pt-Tl(phen)(n)(solv)](+), and (1)J 65.4 kHz (2b) and 62.5 kHz (3b) for n = 1 and 2, respectively, in [(NC)(5)Pt-Tl(phen)(n)(solv)]. The crystal structures of [(NC)(5)Pt-Tl(phen)(DMSO)(3)].(DMSO) (2b), [(NC)(5)Pt-Tl(phen)(2)].(DMSO)(3) (3b), and [Tl(phen)(2)Cl-2] (ClO4) (4) complexes were determined. Very short Pt-Tl bonds, 2.6296(3) and 2.6375(5) Angstrom, are present in structures 2b and 3b, respectively. The corresponding force constants in the molecules in the solid state, 1.84 and 1.74 N/cm for 2b and 3b, respectively, were calculated using Raman stretching frequencies of the Pt-Tl vibrations, and are characteristic for a single, strong metal-metal bond. Electronic absorption spectra were recorded for selected compounds and the optical transition attributed to the metal-metal bond was assigned. ((C) Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002).

  • 24.
    Neranon, Kitjanit
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kinetics and Thermodynamics of Constitutional Dynamic Coordination Systems Based on Fe-II, Co-II, Ni-II, Cu-II, and Zn-II2016In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 24, p. 3950-3956Article in journal (Refereed)
    Abstract [en]

    The self-adaptation of constitutional dynamic systems based on selective coordination between 5,5-dimethyl-2,2-bipyridine and deuterium-labeled 4,4-dimethyl-2,2-bipyridine to Fe-II, Co-II, Ni-II, Cu-II, or Zn-II has been evaluated by ESI-MS in methanol. The equilibration rates of the systems proved dependent on the metal species, following the order Zn-II > Cu-II > Co-II > Ni-II > Fe-II, where Zn-II resulted in rapid rearrangement of the original homoleptic complexes. The heteroleptic complexes were favored in the systems with Co-II, Cu-II and Zn-II, whereas the homoleptic complexes were more pronounced with Fe-II and Ni-II.

  • 25. Olsson, Lars-Fride
    et al.
    Sandin, Karin
    Odselius, Rolf
    Kloo, Lars A.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    In vitro formation of nanocrystalline carbonate apatite - A structural and morphological analogue of atherosclerotic plaques2007In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 26, p. 4123-4127Article in journal (Refereed)
    Abstract [en]

    The in vitro formation of carbonate apatite in solutions with ion concentrations comparable to those in human serum was studied. The composition and morphology of the resulting apatite precipitate displayed a hierarchical assembly of elongated plate-shaped nanocrystals of carbonate apatite analogous to previously characterized bioapatites formed in The main conclusion is that so-called bioapatites may form in vitro and that precipitation inhibitors most likely are essential for the prevention of spontaneous calcification at normal human serum ion concentrations.

  • 26.
    Paulsson, Heléne
    et al.
    KTH, Superseded Departments, Chemistry.
    Berggrund, Malin
    KTH, Superseded Departments, Chemistry.
    Fischer, Andreas
    KTH, Superseded Departments, Chemistry.
    Kloo, Lars A.
    KTH, Superseded Departments, Chemistry.
    Iodoargentates and Cuprates Stabilized by Sulphonium Cations with Long Alkyl Chains2003In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 12, p. 2352-2355Article in journal (Refereed)
    Abstract [en]

    [DodMe2S]22AgI3 and [DodMe2S] Ag2I3 were obtained from mixtures of dodecyldimethylsulfonium iodide and silver iodide in acetonitrile solution. [DodMe2S]2AgI3 crystallizes in the orthorhombic crystal system, space group Pbca and contains trigonal planar anions AgI32-, while [DodMe2S] Ag2I3 crystallizes in the triclinic crystal system, space group P1, and consists of polymeric anions 1(Ag2I3)-. In both structures, the sulfonium cations form a layer of parallel and interpenetrating dodecyl chains with the sulfoniumdimethyl groups on both sides of the layer. [DodMe2S]2CuI3 was obtained from dodecyldimethylsulfonium iodide and copper iodide mixtures and is isostructural with the corresponding silver compound.

  • 27.
    Rosdahl, Jan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Fässler, Thomas F.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    On the Structure of Sn9(4-) Cluster in Liquid and Solid State2005In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 14, p. 2888-2894Article in journal (Refereed)
    Abstract [en]

    The nonastannide clusters have been investigated usingEXAFS, NMR and Raman spectroscopy as well as quantum chemical calculations explicitly considering a model cationic field and solid-state statistics. NMR spectroscopic andEXAFS results are basically identical to those previously published and consistent with a fluctional model of the cluster. The quantum chemical calculations show that there is no significant difference in energy between the two model geometries, C4v and D3h, and that the vibrational frequencies are very low, clearly indicating that the cluster is expected to be fluctional. The solid-state statistics show that both model geometries can be used to describe all known nonastannide structures with reasonable success, illustrating that the classification of the nonastannide clusters in terms of specific symmetries is entirely arbitrary.

  • 28. Sun, Hongfei
    et al.
    Wang, Mei
    Jin, Kun
    Ma, Chengbing
    Zhang, Rong
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Effect of deprotonation of a benzimidazolyl ligand on the redox potential and the structures of mononuclear ruthenium(II) complexes2007In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 26, p. 4128-4131Article in journal (Refereed)
    Abstract [en]

    A monoruthenium(II) complex of the benzimidazolyl ligand and its deprotonated counterpart were prepared and structurally characterized. The reversible protonation/deprotonation process of the ancillary ligand switches the redox potential of the ruthenium(II) core from 0.69 to 0.26 V vs. Ag/AgNO3. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

  • 29. Svensson, P. H.
    et al.
    Raud, G.
    Kloo, Lars
    KTH, Superseded Departments, Chemistry.
    Metal iodides in polyiodide networks - The structural chemistry of complex thallium iodides with excess iodine2000In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 6, p. 1275-1282Article in journal (Refereed)
    Abstract [en]

    The TII/(R3S)I-x systems (R = Me/Et, x = 3,5,7) have been investigated by means of Raman, far-IR, Tl-205 NMR spectroscopy and X-ray diffraction. The reaction between (Me3S)I-7 and TII results in the polyiodide compound (Me3S)(3)I-26 Raman spectra also reveal the presence of a solid thallium- and iodine-containing product. However, all attempts to structurally characterise this product were unsuccessful. The compound (Et3S)TlI4 is obtained from the reaction between (Et3S)I-7 and TlI. Tl-205 NMR spectra show that Tl-III is present in the reaction mixtures of TlI/(R3S)I-x and that the peak assigned to TlI4- in the TlI/(Et3S)I-7 system splits upon heating. This effect is reversible and indicates an equilibrium between two Tl-III species.

  • 30. Troppmann, Stefan
    et al.
    Brandes, Eva
    Motschmann, Hubert
    Li, Fei
    Wang, Mei
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Dalian Univ Technol, China.
    Koenig, Burkhard
    Enhanced Photocatalytic Hydrogen Production by Adsorption of an [FeFe]-Hydrogenase Subunit Mimic on Self-Assembled Membranes2016In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 4, p. 554-560Article in journal (Refereed)
    Abstract [en]

    Self-assembled vesicles with membrane-embedded or adsorbed ruthenium polypyridine complexes were further functionalized by the adsorption of an [FeFe]-hydrogenase subunit mimic to the membrane interface enhancing the photocatalytic hydrogen production in water under acidic conditions. The resulting two-dimensional membrane assembly places the photosensitizer and hydrogen-evolving diiron complex in close proximity resulting in a six-to twelvefold increase in the turnover number as compared to the same system in the absence of lipid membranes. The interface assembly then enables the combining of hydrophilic and hydrophobic catalytic entities for light-driven proton reduction in acidic water and provides a flexible method for membrane functionalization.

  • 31. Ulvenlund, Stefan
    et al.
    Rosdahl, Jan
    KTH, Superseded Departments, Chemistry.
    Fischer, Andreas
    KTH, Superseded Departments, Chemistry.
    Schwerdtfeger, Peter
    Kloo, Lars
    KTH, Superseded Departments, Chemistry.
    Hard Acid and Soft Base Stabilisation of Di- and Trimercury Cations in Benzene Solution - A Spectroscopic, X-ray Scattering, and Quantum Chemical Study1999In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 4, p. 633-642Article in journal (Refereed)
    Abstract [en]

    Hg2Cl2 dissolves in GaCl3/benzene solution to yield Hg-2(2+) and chlorogallate(III) ions, GanCl3n+1-. In such solutions, Hg-2(2+) can be reduced to Hg-3(2+) by metallic mercury. Solubility measurements show that one mol of Hg is oxidised per mol of Hg-2(2+). The Hg-3(2+) ion gives a strong band at 110 cm(-1) in the Raman spectrum and Hg-Hg correlations at about 2.60 and 5.15 Angstrom in the radial distribution function obtained by Liquid X-ray scattering. - Hg-3(2+) can also be synthesised in high yield by direct oxidation of metallic mercury by Ga-III in GaCl3/benzene solution. In contrast, mercury is insoluble in neat Liquid GaCl3 and only sparingly soluble in GaCl3/KCl melts. It therefore seems likely that the thermodynamic stabilisation of subvalent mercury species in benzene solution not only relies on the traditional acid stabilisation provided by the hard Lewis acid GaCl3, but also on a "soft-base stabilisation" provided by interactions between the aromatic molecules and the cations. Evidence for such specific interactions between Hg-m(2+) cations and C6H6 are observed in the Raman spectra: The totally symmetric C6H6 band at 991 cm(-1) is found to split in the presence of Hg-m(2+) ions and to give new peaks at 978 (m = 2) and 982 (m = 3) cm(-1). - In order to further elucidate the cluster-arene interactions, ab initio and density functional calculations were performed for the model compounds Hg-m(C6H6)(2)(2+) and HgmCl2(C6H6)(2), m = 2 and 3. The calculations show that both models represent coordinations modes which are feasible for Hg-m(2+) ions. However, the calculated vibrational frequencies for the Hg-m(C6H6)(2)(2+) models with eta(1)/quasi-eta(3) coordination of the benzene molecules along the Hg-Hg vector are most consistent with the body of experimental and literature data. The counterions are thus suggested to occupy secondary coordination sites.

  • 32.
    Åkerstedt, Josefin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Ponou, Simeon
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Inorganic Chemistry.
    Lidin, Sven
    Structural Investigation of a Fully Ordered closo-Ge(9)(2-) Cluster in the Compound [K(+)(2,2,2-crypt)](2)Ge(9)(2-)2011In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, no 26, p. 3999-4005Article in journal (Refereed)
    Abstract [en]

    [K(+)(2,2,2-crypt)] (2)Ge(9)(2-) containing the deltahedral Zintl anion Ge(9)(2-) has been isolated from a solution of K(4)Ge(9) in ethylenediamine in the presence of 2,2,2-crypt, intended as an intermediate in mixed-cluster synthesis. The subsequent crystallographic characterisation shows the closo-Ge(9)(2-) cluster unit to be tricapped trigonal-prismatic with a symmetry very close to D(3h). Each Ge(9)(2-) unit is surrounded by two 2,2,2-crypt units, each with a chelated K(+) cation, viz. [K(+)(2,2,2-crypt)]. The structure characterisation of this ordered Ge(9)(2-) cluster is surprisingly enough the first one reported. A chemical bonding analysis reveals two local minima of D(3h) symmetry, with that of lowest energy being highly similar to that resulting from the crystallographic analysis of low-temperature data. The cluster interaction scheme is based on highly delocalised bonding.

1 - 32 of 32
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf