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Journal articles on the topic 'Metal-metal quadruple bonds'

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Published: 4 June 2021

Last updated: 2 February 2022

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1

Chisholm, Malcolm H., Arthur J. Epstein, Judith C. Gallucci, Florian Feil, and Wesley Pirkle. "Oligothiophenes Incorporating Metal-Metal Quadruple Bonds." Angewandte Chemie International Edition 44, no. 40 (October 14, 2005): 6537–40. http://dx.doi.org/10.1002/anie.200500138.

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Chisholm, Malcolm H., Arthur J. Epstein, Judith C. Gallucci, Florian Feil, and Wesley Pirkle. "Oligothiophenes Incorporating Metal-Metal Quadruple Bonds." Angewandte Chemie 117, no. 40 (October 14, 2005): 6695–98. http://dx.doi.org/10.1002/ange.200500138.

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3

Li, Ming. "Study on some metal-metal quadruple bonds." International Journal of Quantum Chemistry 43, no. 3 (July 20, 1992): 343–52. http://dx.doi.org/10.1002/qua.560430305.

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4

Chisholm, Malcolm H. "Mixed valency and metal–metal quadruple bonds." Coordination Chemistry Reviews 257, no. 9-10 (May 2013): 1576–83. http://dx.doi.org/10.1016/j.ccr.2012.10.021.

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5

Kerby, Michael C., Bryan W. Eichhorn, Loriann Doviken, and K. Peter C. Vollhardt. "Activated molybdenum-molybdenum quadruple bonds. 2. First example of alkyne additions to metal-metal quadruple bonds." Inorganic Chemistry 30, no. 2 (January 1991): 156–58. http://dx.doi.org/10.1021/ic00002a003.

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6

Hua, Shao-An, Yi-Chou Tsai, and Shie-Ming Peng. "A Journey of Metal-metal Bonding beyond Cotton's Quadruple Bonds." Journal of the Chinese Chemical Society 61, no. 1 (October 22, 2013): 9–26. http://dx.doi.org/10.1002/jccs.201300417.

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7

Ismayilov, Rayyat H., Wen-Zhen Wang, Rui-Ren Wang, Chen-Yu Yeh, Gene-Hsiang Lee, and Shie-Ming Peng. "Four quadruple metal–metal bonds lined up: linear nonachromium(ii) metal string complexes." Chem. Commun., no. 11 (2007): 1121–23. http://dx.doi.org/10.1039/b614597c.

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8

KERBY, M. C., B. W. EICHHORN, L. DOVIKEN, and K. P. C. VOLLHARDT. "ChemInform Abstract: Activated Molybdenum-Molybdenum Quadruple Bonds. Part 2. First Example of Alkyne Additions to Metal-Metal Quadruple Bonds." ChemInform 22, no. 20 (August 23, 2010): no. http://dx.doi.org/10.1002/chin.199120234.

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9

Cotton, F. Albert. "Metal-metal quadruple bonds: New frontiers for their kith and kin." Journal of Cluster Science 5, no. 1 (March 1994): 3–9. http://dx.doi.org/10.1007/bf01165489.

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10

Dalal, Naresh S., and Carlos A. Murillo. "The usefulness of EPR spectroscopy in the study of compounds with metal–metal multiple bonds." Dalton Trans. 43, no. 23 (2014): 8565–76. http://dx.doi.org/10.1039/c4dt00506f.

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A discussion of how EPR spectroscopy has contributed to the understanding of the electronic structure of paddlewheel compounds with multiple bonds between metal atoms is presented while commemorating the 50th anniversary of the paper describing the quadruple bond and the identification of the delta bond in the Re₂Cl₈²⁻ anion.

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Cayton, Roger H., and Malcolm H. Chisholm. "Electronic coupling between covalently linked metal-metal quadruple bonds of molybdenum and tungsten." Journal of the American Chemical Society 111, no. 24 (November 1989): 8921–23. http://dx.doi.org/10.1021/ja00206a027.

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COTTON, F. A. "ChemInform Abstract: Metal-Metal Quadruple Bonds: New Frontiers for Their Kith and Kin." ChemInform 25, no. 42 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199442293.

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Hua, Shao-An, Yi-Chou Tsai, and Shie-Ming Peng. "ChemInform Abstract: A Journey of Metal-Metal Bonding Beyond Cotton′s Quadruple Bonds." ChemInform 45, no. 14 (March 21, 2014): no. http://dx.doi.org/10.1002/chin.201414241.

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14

Larson, E. M., T. M. Brown, and R. B. Von Dreele. "Normal coordinate analysis of metal–metal quadruple bonds using a more complete force field." Acta Crystallographica Section B Structural Science 42, no. 6 (December 1, 1986): 533–38. http://dx.doi.org/10.1107/s0108768186097744.

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Carrasco, Mario, Irene Mendoza, Michelle Faust, Joaquín López-Serrano, Riccardo Peloso, Amor Rodríguez, Eleuterio Álvarez, Celia Maya, Philip P. Power, and Ernesto Carmona. "Terphenyl Complexes of Molybdenum and Tungsten with Quadruple Metal–Metal Bonds and Bridging Carboxylate Ligands." Journal of the American Chemical Society 136, no. 25 (June 11, 2014): 9173–80. http://dx.doi.org/10.1021/ja503750a.

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16

Attia, Amr A. A., Alexandru Lupan, and R. Bruce King. "Metal–metal bonding in deltahedral dimetallaboranes and trimetallaboranes: a density functional theory study." Pure and Applied Chemistry 90, no. 4 (March 28, 2018): 643–52. http://dx.doi.org/10.1515/pac-2017-0906.

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AbstractThe skeletal bonding topology as well as the Re=Re distances and Wiberg bond indices in the experimentally knownoblatoclosodirhenaboranes Cp*2Re2Bn−2Hn−2(Cp*=η5Me5C5,n=8–12) suggest formal Re=Re double bonds through the center of a flattened Re2Bn−2deltahedron. Removal of a boron vertex from theseoblatoclosostructures leads tooblatonidostructures such as Cp2W2B5H9and Cp2W2B6H10. Similar removal of two boron vertices from the Cp2Re2Bn−2Hn−2(n=8–12) structures generatesoblatoarachnostructures such as Cp2Re2B4H8and Cp2Re2B7H11. Higher energy Cp2Re2Bn−2Hn−2(Cp=η5-C5H5,n=8–12) structures exhibitclosodeltahedral structures similar to the deltahedral borane dianions BnHn2−. The rhenium atoms in these structures are located at adjacent vertices with ultrashort Re≣Re distances similar to the formal quadruple bond found in Re2Cl82−by X-ray crystallography. Such surface Re≣Re quadruple bonds are found in the lowest energy PnRe2Bn−2Hn−2structures (Pn=η5,η5-pentalene) in which the pentalene ligand forces the rhenium atoms to occupy adjacent deltahedral vertices. The low-energy structures of the tritungstaboranes Cp3W3(H)Bn−3Hn−3(n=5–12), related to the experimentally known Cp*3W3(H)B8H8, have central W3Bn−3deltahedra with imbedded bonded W3triangles. Similar structures are found for the isoelectronic trirhenaboranes Cp3Re3Bn−3Hn−3. The metal atoms are located at degree 6 and 7 vertices in regions of relatively low surface curvature whereas the boron atoms are located at degree 3–5 vertices in regions of relatively high surface curvature. The five lowest-energy structures for the 11-vertex tritungstaborane Cp3W3(H)B8H8all have the same central W3B8deltahedron and differ only by the location of the “extra” hydrogen atom. The isosceles W3triangles in these structures have two long ~3.0 Å W–W edges through the inside of the deltahedron with the third shorter W–W edge of ~2.7 to ~2.8 Å corresponding to a surface deltahedral edge.

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Nishino, Masamichi, Kazushi Mashima, Sadamu Takeda, Mitsuhiro Tanaka, Wasuke Mori, Kazuhide Tani, Akira Nakamura, and Kizashi Yamaguchi. "Casci and Casscf Studies of Dinuclear Transition Metal Systems with Quadruple Metal-Metal Bonds (M=Cr(Ii), Mo(Ii))." Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals 306, no. 1 (October 1997): 321–30. http://dx.doi.org/10.1080/10587259708044583.

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18

Cayton, Roger H., Malcolm H. Chisholm, and Frank D. Darrington. "Multiple Bonds Between Metal Atoms in Ordered Assemblies: Liquid Crystals Containing MoMo Quadruple Bonds." Angewandte Chemie International Edition in English 29, no. 12 (December 1990): 1481–83. http://dx.doi.org/10.1002/anie.199014811.

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19

Tang, Lihong, Qiong Luo, Qian-shu Li, Yaoming Xie, R. Bruce King, and Henry F. Schaefer. "The Quest for Metal–Metal Quadruple and Quintuple Bonds in Metal Carbonyl Derivatives: Nb2(CO)9 and Nb2(CO)8." Journal of Chemical Theory and Computation 8, no. 3 (February 16, 2012): 862–74. http://dx.doi.org/10.1021/ct200820v.

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20

Pan, Sudip, Sai Manoj, and Gernot Frenking. "Quadruple bonding of bare group-13 atoms in transition metal complexes." Dalton Transactions 49, no. 42 (2020): 14815–25. http://dx.doi.org/10.1039/d0dt02773a.

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Bonding analysis shows that E–TM(CO)₃^q bonds possess four bonding components: one strong electron-sharing σ bond E–TM(CO)₃^q, two π backdonations E⇇TM(CO)₃^q and one weak σ donation E→TM(CO)₃^q.

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21

Cayton, Roger H., Malcolm H. Chisholm, John C. Huffman, and Emil B. Lobkovsky. "Metal-metal multiple bonds in ordered assemblies. 1. Tetranuclear molybdenum and tungsten carboxylates involving covalently linked metal-metal quadruple bonds. Molecular models for subunits of one-dimensional stiff-chain polymers." Journal of the American Chemical Society 113, no. 23 (November 1991): 8709–24. http://dx.doi.org/10.1021/ja00023a019.

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22

Takagi, Nozomi, Andreas Krapp, and Gernot Frenking. "On the nature of homo- and hetero-dinuclear metal–metal quadruple bonds — Analysis of the bonding situation and benchmarking DFT against wave function methods." Canadian Journal of Chemistry 88, no. 11 (November 2010): 1079–93. http://dx.doi.org/10.1139/v10-078.

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Homo- and hetero-dimetallic (d–d)8 analogues of the formally quadruply bonded [Re2Cl8]2– system with the general formula [MM′Cl8]x (M, M′ = Tc, Re, Ru, Os, Rh, Ir and x = –2, –1, 0, +1, +2) have been calculated with the density functional theory (DFT) functionals SVWN, BLYP, BP86, PBE, OLYP, OPBE, HCTH, B3LYP, O3LYP, X3LYP, BH&HLYP, TPSS, VSXC, TPPSh, and ab initio methods (CASPT2, CCSD(T)) using basis sets of triple-ζ quality. The performance of the functionals for the description of the metal–metal bond distance and the bond dissociation energy as well as the singlet–triplet gap was evaluated with respect to ab initio data at the CASPT2 level. Generally, the generalized gradient approximation (GGA) functionals, BLYP, BP86, and PBE, show good performance in the description of the metal–metal bond distance and for the dissociation energy. Hybrid functionals are not to be used for compounds of the type discussed here as they lead to increasingly too short and too weak bonds with the amount of exact exchange included. All functionals underestimate the singlet–triplet gap, with the GGA functionals BLYP, BP86, PBE being the closest to the CASPT2 values. The bonding situations of the [MM′Cl8]x compounds were analyzed at the DFT level (BP86) using the natural bond orbital (NBO) method and the energy decomposition analysis. The M–M bond in homodimetallic compounds, [MMCl8]x, becomes weaker from group 7 to group 8 to group 9 metals and the bond is weaker for 4d metal systems than for 5d transition metal compounds. The M–M bonds have approximately 50% covalent and 50% electrostatic character and the covalent contribution is dominated by the π orbitals, whereas the δ orbitals do not contribute significantly to the covalent bonding. Heterodimetallic systems, [MM′Cl8]x, have significantly stronger metal–metal bonds than the homodimetallic compounds. This comes from weaker Pauli repulsion and stronger electrostatic attraction. The most stable heterodimetallic bonds are observed for 5d–5d metal pairs.

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23

Sunderland, Travis L., and John F. Berry. "Metal-Metal Single Bonds with the Magnetic Anisotropy of Quadruple Bonds: A Systematic Series of Heterobimetallic Bismuth(II)-Rhodium(II) Formamidinate Complexes." Chemistry - A European Journal 22, no. 51 (November 3, 2016): 18564–71. http://dx.doi.org/10.1002/chem.201604007.

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24

CAYTON, R. H., M. H. CHISHOLM, and F. D. DARRINGTON. "ChemInform Abstract: Multiple Bonds Between Metal Atoms in Ordered Assemblies: Liquid Crystals Containing Mo-Mo Quadruple Bonds." ChemInform 22, no. 10 (August 23, 2010): no. http://dx.doi.org/10.1002/chin.199110330.

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25

Đorđević, Tamara, and Ljiljana Karanović. "An update on the mineral-like Sr-containing transition metal arsenates." Mineralogical Magazine 85, no. 3 (May 26, 2021): 416–30. http://dx.doi.org/10.1180/mgm.2021.41.

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AbstractWe report on the crystal structures of three novel synthetic SrM-arsenates (M = Ni and Fe3+), isostructural or structurally related to the minerals from tsumcorite, carminite and brackebuschite groups. They were synthesised under mild hydrothermal conditions and further characterised using single-crystal X-ray diffraction (SXRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and Raman spectroscopy. SXRD and SEM-EDS yielded formulae: (I) SrNi2(AsO4)2⋅2H2O, (II) Sr1.4Fe3+1.6(AsO4)2(OH)1.6 and (III) SrFe3+(AsO4)(AsO3OH). All three structures are built up of slightly distorted MO6 octahedra and AsO4 tetrahedra that are linked by Sr2+ with different coordination geometries and hydrogen bonds. I represent a basic structure type typical for tsumcorite-group minerals (space group C2/m) while II has a new intermediate structure between carminite, PbFe3+2(AsO4)2(OH)2 and arsenbrackebuschite, Pb2Fe3+(AsO4)2(OH) (s.g. Pm). III is triclinic and adopts a new structure-type (s.g. P$\bar{1}$). The structure of I is built up of infinite linear edge-sharing NiO4(OH2)2 octahedral chains, extending along [010] and linked by AsO4 tetrahedra, SrO8 polyhedra and hydrogen bonds. The structure of II is characterised by the carminite-like FeO4(OH)2 octahedral chains and Edshammar-polyhedral chains, which involves SrO11 coordination polyhedra similar to that of PbO11 in arsenbrackebuschite. Both chains in II are aligned parallel to the b axis of the monoclinic unit cell and connected together by the arsenate AsO4 tetrahedra, SrO8 polyhedra and the hydrogen-bonding network. The compound III has a new type of crystal structure based on the unusual corrugated octahedral–tetrahedral-quadruple chains. These are made up of a central double-sided chain linked to two single-sided chains into a quadruple chain extended along the a axis. The chains in III are built up of FeO6 octahedra and AsO4 tetrahedra further linked to each other by shared vertices. The quadruple chains are interconnected by additional AsO4 tetrahedra forming a heteropolyhedral 3D open framework. Strontium atoms are situated in the two channels. The structural connections to related minerals and inorganic compounds are discussed.

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Shtemenko, Alexander V., Alexander A. Golichenko, and Konstantin V. Domasevitch. "Synthesis of Novel Tetracarboxylato Dirhenium(III) Compounds and Crystal Structure of [Re2(1-Adamantylcarboxylate)4Cl2] · 4 CHCl3." Zeitschrift für Naturforschung B 56, no. 4-5 (May 1, 2001): 381–85. http://dx.doi.org/10.1515/znb-2001-4-510.

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Abstract The coordination compounds o f the general formula Re2 (L)4X2 (X = Cl, Br; L = 1 -adamantyl-carboxylate and 1 -adamantylacetate) have been prepared and characterized by means of UV-VIS spectroscopy (20000 cm-1 , δ → δ*). The crystal and molecular structure of Re2(AdCOO)4Cl2 · 4 CHCl3 solvate was determined by X-ray diffraction. The units Re2(AdCOO)4Cl2 adopt a centrosymmetric dinuclear array with each metal atom coordinated in a distorted octahedron comprising one rhenium and one chlorine atoms (Re-Cl 2.505(2) Å) and four carboxylate oxygen atoms in the equatorial plane. The rhenium-rhenium separation of 2.2300(5) Å corresponds to quadruple bond between the metal atoms. All R e-0 bonds have an almost uniform length (2.017(4) -2.032(4) Å) and do not differ essentially from the parameters reported for related compounds. The closest environment of the Re2(AdCOO)4Cl2 molecules in the crystal comprises weak Cl---HC hydrogen bonds with the chloroform molecules and significantly shortened van der Waals contacts Cl---Cl, 3.46 Å.

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27

Chisholm, Malcolm H., and Christopher J. Ziehm. "Metal–Metal Quadruple Bonds (M = Mo or W) Supported by 4-[2-(4-Pyridinyl)ethenyl] Benzoates and their Complexes with Tris(pentafluorophenyl)boron." Inorganic Chemistry 54, no. 23 (November 23, 2015): 11168–73. http://dx.doi.org/10.1021/acs.inorgchem.5b01520.

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28

Lichtenberger, Dennis L., Matthew A. Lynn, and Malcolm H. Chisholm. "Quadruple Metal−Metal Bonds with Strong Donor Ligands. Ultraviolet Photoelectron Spectroscopy of M2(form)4(M = Cr, Mo, W; form =N,N‘-diphenylformamidinate)." Journal of the American Chemical Society 121, no. 51 (December 1999): 12167–76. http://dx.doi.org/10.1021/ja993065e.

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29

Brown-Xu, Samantha E., Malcolm H. Chisholm, Christopher B. Durr, and Thomas F. Spilker. "Metal–Metal Quadruple Bonds Supported by 5-Ethynylthiophene-2-carboxylato Ligands: Preparation, Molecular and Electronic Structures, Photoexcited State Dynamics, and Application as Molecular Synthons." Journal of the American Chemical Society 135, no. 22 (May 24, 2013): 8254–59. http://dx.doi.org/10.1021/ja400508u.

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30

Takagi, Nozomi, Andreas Krapp, and Gernot Frenking. "ChemInform Abstract: On the Nature of Homo- and Hetero-Dinuclear Metal-Metal Quadruple Bonds - Analysis of the Bonding Situation and Benchmarking DFT Against Wave Function Methods." ChemInform 42, no. 9 (February 3, 2011): no. http://dx.doi.org/10.1002/chin.201109001.

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31

Byrnes, Matthew J., Malcolm H. Chisholm, and Nathan J. Patmore. "New Metal−Organic Polygons Involving MM Quadruple Bonds: M8(O2CtBu)4(μ-SC4H2-3,4-{CO2}2)6(M = Mo, W)." Inorganic Chemistry 44, no. 25 (December 2005): 9347–52. http://dx.doi.org/10.1021/ic051516s.

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32

Ndambuki, Sylvester, and Tom Ziegler. "An analysis of unsupported triple and quadruple metal-metal bonds between two homonuclear group 6 transition elements based on the combined natural orbitals for chemical valence and extended transition state method." International Journal of Quantum Chemistry 113, no. 6 (April 17, 2012): 753–61. http://dx.doi.org/10.1002/qua.24068.

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33

Cotton, F. Albert, and Rinaldo Poli. "Thermal reaction of octacarbonyltetraiododimolybdenum with dimethylphenylphosphine, diethylphenylphosphine and pyridine. Formation of metal-metal quadruple bonds vs. disproportionation. X-ray crystal structures of bis(dimethylphenylphosphine)(dimethylphenylphosphine oxide)triiodomolybdenum and diethylphenylphosphonium bis(diethylphenylphosphine)tetraiodomolybdate(1-)." Inorganic Chemistry 25, no. 20 (September 1986): 3624–29. http://dx.doi.org/10.1021/ic00240a019.

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34

Zhang, Xuan, Hanhua Zhao, Lukas Palatinus, Kevin Gagnon, John Bacsa, and Kim Dunbar. "Semiconductors and Aperiodic Structures in Organocyanide-Based Materials." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1265. http://dx.doi.org/10.1107/s2053273314087348.

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Organocyanides such as TCNQ (tetracyanoquinodimethane) and DCNQI (dicyanoquinodiimine) are excellent electron acceptors and have been extensively studied in electrically conducting/switching and magnetic materials. Supramolecular interactions such as π-stacking and hydrogen bonding in addition to coordination bonds with metal ions play an important role in the self-assembly of these functional inorganic materials. A novel semiconductor Cd2(TCNQ)3.5(H2O)2 with non-integer valences of TCNQ was synthesized and is the first example that exhibits four bridging modes of TCNQ in one structure (Figure 1). Despite the rather large stacking distance of 3.687(1) Å between the two μ3-TCNQ species, which constitute a "broken link" in the electron conducting pathway, the semiconductor exhibits a room temperature conductivity of 5.8×10-3 S·cm-1. The hydrogen bonding interactions between the coordinated water molecules and nitrogen atoms of the mu2- and mu3-TCNQ help to stabilize these coordinatively unsaturated TCNQ species. Another application of the chemistry of organocyanides in the context of this research is the study of reactions of the meta-dicyanamidobenzene dianion (DCYD2-) which was predicted by Ruiz and coworkers to facilitate ferromagnetic interactions between certain paramagnetic metal ions. The DCYD2- anion self-assembles with Mn(II) building blocks to afford a rare example of inorganic quadruple helices with an incommensurate modulated structure (Figure 2a). A supercell in the high symmetry space group P4/nnc is obtained with a c parameter five times that of the basic structure and a further 15-fold expansion in the space group of P1 along the c axis reveals that ~2% of Mn positions are disordered. The packing of these helical chains through π-stacking of pyridyl groups leads to 1D nanochannels with an estimated empty volume of 38.6% of the super cell volume (31,587Å3). However, in the presence of water, hydrogen bonding between the water molecules and the cyano-N atoms dominates and only zig-zag chains are formed (Figure 2b).

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Delmonte, Davide, Francesco Mezzadri, Chiara Pernechele, Massimo Solzi, Gianluca Calestani, Fulvio Bolzoni, Riccardo Cabassi, and Edmondo Gilioli. "HP/HT synthesis and characterization of novel multiferroic Bi-based perovskites." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1815. http://dx.doi.org/10.1107/s2053273314081856.

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Bi-based perovskites (BiM1-xM'xO3, where M e M' are 3d and 4d metal ions) are considered very promising candidates to show multiferroic magnetoelectric character. A multiferroic magnetoelectric is a material in which ferromagnetism and ferroelectricity are not only coexistent but also coupled. Such properties, very rare in natural materials, are suitable for electronics, data storage and spintronics applications. Therefore, the interest in this class of compound showed an increasing trend of scientific publications in the last ten years. Unfortunately most members of this family cannot be synthesized with conventional techniques, due to their highly unstable and distorted crystallographic structure. High isostatic pressures and high temperatures can be exploited to overcome this fundamental drawback. The strategy is to induce ferroelectricity (e.g. polar symmetry) achieving the stereochemical effect of Bi3+ 6s2 lone pair, that polarizes the bonds with the neighboring oxygen anions, and independently to bring magnetism through the introduction of magnetic ions of the third or the fourth period on the octahedral coordinated B-site of the perovskite structure. We have synthesized simple and complex (quadruple [1,2] and double [3]) Bi-based perovskites in wide ranges of pressure (from 3 to 9 GPa) and temperature (from 9000C to 16500C) by means of solid state reactions in a multi-anvil Walker-type Press. We present an accurate study of the structural, magnetic and electric properties. Furthermore, unconventional home-made set-ups are also presented as the tools to probe the coupling between the electric and the magnetic properties through crossed magnetic characterizations (magnetic susceptibility dependence on an applied electric field) and reversely crossed electric characterizations (polarization as a function of an external magnetic field).

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36

Cole, Nancy F., Daniel R. Derringer, Elizabeth A. Fiore, Donald J. Knoechel, Rebecca K. Schmitt, and Thomas J. Smith. "Reactions of chloro complexes of dimolybdenum(II) containing quadruple metal-metal bonds with bidentate tertiary phosphines (C6H5)2P(CH2)nP(C6H5)2 (n = 1-3) and (C6H5)2P(CH2)2As(C6H5)2 in alcohol media. Effect of ligand hydrocarbon chain length and solvent on product formation and isomerization." Inorganic Chemistry 24, no. 13 (June 1985): 1978–82. http://dx.doi.org/10.1021/ic00207a006.

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37

Baxter, David V., Roger H. Cayton, Malcolm H. Chisholm, John C. Huffman, Elena F. Putilina, Sandra L. Tagg, Jodi L. Wesemann, Josef W. Zwanziger, and Frank D. Darrington. "Multiple Bonds between Metal Atoms in Ordered Assemblies. 2. Quadrupole Bonds in the Mesomorphic State." Journal of the American Chemical Society 116, no. 11 (June 1994): 4551–66. http://dx.doi.org/10.1021/ja00090a003.

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38

Ghiasi, Reza, and Nasrin Sadeghi. "Evolution of the interaction between C20 cage and Cr(CO)5: A solvent effect, QTAIM and EDA investigation." Journal of Theoretical and Computational Chemistry 16, no. 01 (February 2017): 1750007. http://dx.doi.org/10.1142/s0219633617500079.

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This study used mpw1pw91 quantum chemical calculations in gas and solution phases to clarify the interaction between C20 and Cr(CO)5 fragment. It also sought to clarify the effects of solvent polarity on dipole moment, structural parameters, and frontier orbital energies of the complex. Energy decomposition analysis (EDA) was applied to analyze the bonding interaction between the C20 and Cr(CO)5 fragment. Percentage composition in terms of the defined groups of frontier orbitals for the complex was evaluated to characterize the metal–ligand bonds. The Cr–C bonds within the complex were examined using quantum theory of atoms in molecules (QTAIM) analysis. In order to determine the back-bonding effects in these bonds, QTAIM analysis was applied to calculate of the quadrupole polarization of the carbon atom.

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39

Marwah, Padma, Ashok K. Marwah, and Paul V. Zimba. "Controlling formation of metal ion adducts and enhancing sensitivity in Liquid Chromatography Mass Spectrometry." Journal of Applied and Natural Science 12, no. 2 (June 1, 2020): 180–92. http://dx.doi.org/10.31018/jans.vi.2277.

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Formation of metal ion adducts in mass spectrometry, particularly in electrospray ionization liquid chromatography mass spectrometry (ESI-LC-MS), is a nightmare scenario for an analyst dealing with quantitative analysis. We have studied in detail the metal adduct formation and concluded that the use of fluorinated alkanoic acids along with formic acid and volatile ammonium salts was extremely useful in suppressing metal adduct formation in positive ion mode of ESI-LC-MS. The extremely high electronegativity of fluorine atom and unique electrostatic nature of C—F bond coupled with stereo-electronic interactions with neighboring bonds or lone pairs enables the polyfluorinated alkanoic acids in trapping highly electropositive ions (Na+, K+) thereby letting proton do its job efficiently. Addition of formic acid, trifluoroacetic acid, heptafluorobutyric acid and ammonium acetate was found to be extremely effective in controlling metal ion adducts and producing [M+H]+ ions almost exclusively resulting in significant increase in the sensitivity. This technique has been successfully used in our laboratory for the estimation of targeted and nontargeted analysis of pesticides, marine toxins, drugs and pharmaceuticals etc. in various matrices including environmental waters using liquid chromatography-time of flight mass spectrometer operated in all ion acquisition mode and triple quadruples (QQQ) in multiple reaction monitoring (MRM) mode.

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40

Suzuki, Atsushi, and Takeo Oku. "Electronic Structures, Spectroscopic Properties, and Thermodynamic Characterization of Alkali Metal and Transition Metal Incorporated Perovskite Crystals by First-Principles Calculation." Materials Proceedings 4, no. 1 (November 11, 2020): 79. http://dx.doi.org/10.3390/iocn2020-07942.

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The influence of alkali metals (Na, K) or transition metals (Co, Cr, Cu, and Y) incorporated into perovskite crystal on the electronic structures, spectroscopic, and magnetic properties, and thermodynamic properties was investigated by first-principles calculation. Incorporation of Na or K into the perovskite crystal generated 3s, 3p, 4s, and 4p orbitals of Na or K above the conduction band, which promoted the charge transfer from alkali metal to the conduction band, accelerating the electron diffusion related to the photovoltaic properties. For the Cr, Cu, and Y-incorporated perovskite crystals, the electron density distribution of d-p hybrid orbital on the transition metal and iodine halogen ligand were delocalized at frontier orbital. The electronic correlation worked in between the localized spin on 3d orbital of the metal, and the itinerant carriers on the 5p orbital of the iodine halogen ligand and the 6p orbital of the lead atom in the perovskite crystal. The vibration behavior of the Raman and infrared spectra were associated with change of polarization and slight distortion near the coordination structure. The considerable splitting of chemical shift of 127I-NMR and 207Pb-NMR in the magnetic field was caused by crystal field splitting with the Jahn-Teller effect with nearest-neighbor nuclear quadrupole interaction based on the charge distribution. Decrease of the Gibbs free energy and entropy indicated the thermodynamic stabilization without scattering carrier diffusion as phonon effectiveness. The decrease of the entropy was based on a slight change of stretching vibration mode of Pb–I bond with vending mode of N–H and C–H bonds in the infrared and Raman spectra. The minor addition of alkali metal or transition metal into the perovskite crystal would improve the photovoltaic properties, open voltage related to band gap, and short-circuit current density based on the carrier diffusion with phonon effectiveness.

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41

Soheyli, Ehsan, Mohammad Hossein Hekmatshoar, and Farshad Parcham. "Optical and structural characterization of quadruplet and quintuplet molybdenum-containing phosphate glasses." Modern Physics Letters B 30, no. 18 (July 10, 2016): 1650270. http://dx.doi.org/10.1142/s0217984916502705.

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In this work, vitreous samples were prepared in two series by normal melt-quenching technique and under controlled conditions. The amorphous nature of specimens was confirmed using XRD spectra. To perform FT-IR and UV-vis studies, the thin blown films were also prepared. Different ratios of transition metals are assumed to cause depolymerization of the phosphate glass network. Infrared spectra showed absorption bands related to characteristic bonds of phosphate. The P=O bond at about 1200 cm[Formula: see text] was observed, as a direct consequence of meta-phosphate bond group. The almost unchanged peak position and intensity of P=O bond (in the presence of two transition metal ions) indicated the glass modifying nature of transition metal oxides (TMOs). The spectra of two series are almost identical, except for 890–1100 cm[Formula: see text] range, which can be attributed to presence of second TMO in the first glass series. UV-vis spectra also showed that the absorption edge, optical band gap and Urbach energy of the prepared samples are highly dependent on the kind and percentage of their reagents. The most striking result of UV-vis measurements was increasing and decreasing of optical band gap in the first and the second series with MoO3 content, respectively. The shape of the absorption edge (a plot of [Formula: see text] versus [Formula: see text]) demonstrated the indirect nature of the band gap in the prepared specimens.

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Suzuki, Atsushi, and Takeo Oku. "Electronic structures and magnetic properties of transition metal doped CsPbI-=SUB=-3-=/SUB=- perovskite compounds by first-principles calculation -=SUP=-*-=/SUP=-." Физика твердого тела 61, no. 6 (2019): 1150. http://dx.doi.org/10.21883/ftt.2019.06.47692.004.

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AbstractTransition metal doped cesium lead halide (CsPbI_3) perovskite compounds were studied for application in photovoltaic solar cells. Electronic structures, chemical shifts of ^207Pb and ^127I-NMR, vibration modes in infrared and Raman spectra of transition metals (Mn^2+, Fe^2+ or Cu^2+)-doped CsPbI_3 perovskite compounds were studied by the first-principles calculation using density functional theory. The CsPb(Fe)I_3 perovskite crystals had a slight perturbation of crystal field in the coordination structure. The electron density distribution was delocalized on the 5 p orbital of I atom, the 3 d orbital of Fe atom and the 6 p orbital of Pb atom. The first excited process was based on ligand metal charge transfer from the 5 p orbital on I atom to the 3 d orbital of Fe atom. The chemical shifts of ^127I-NMR were associated with the electron correlation of electron-nuclear spin interaction and nuclear quadrupole interactions based on electron field graduate. The asymmetric vibrations of Pb–I bonds stretching mode related to electron conductivity with scattering of the carrier diffusion as phonon effectiveness. The slight perturbation of the coordination structure in the CsPb(Fe)I_3 perovskite crystal will improve the photovoltaic and optical properties.

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43

Evans, Corey J., Alberto Lesarri, and Michael C. L. Gerry. "Noble Gas−Metal Chemical Bonds. Microwave Spectra, Geometries, and Nuclear Quadrupole Coupling Constants of Ar−AuCl and Kr−AuCl." Journal of the American Chemical Society 122, no. 25 (June 2000): 6100–6105. http://dx.doi.org/10.1021/ja000874l.

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44

Chi, Chaoxian, Jia-Qi Wang, Han-Shi Hu, Yang-Yang Zhang, Wan-Lu Li, Luyan Meng, Mingbiao Luo, Mingfei Zhou, and Jun Li. "Quadruple bonding between iron and boron in the BFe(CO)3− complex." Nature Communications 10, no. 1 (October 17, 2019). http://dx.doi.org/10.1038/s41467-019-12767-5.

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Abstract While main group elements have four valence orbitals accessible for bonding, quadruple bonding to main group elements is extremely rare. Here we report that main group element boron is able to form quadruple bonding interactions with iron in the BFe(CO)3- anion complex, which has been revealed by quantum chemical investigation and identified by mass-selected infrared photodissociation spectroscopy in the gas phase. The complex is characterized to have a B-Fe(CO)3− structure of C3v symmetry and features a B-Fe bond distance that is much shorter than that expected for a triple bond. Various chemical bonding analyses indicate that the complex involves unprecedented B≣Fe quadruple bonding interactions. Besides the common one electron-sharing σ bond and two Fe→B dative π bonds, there is an additional weak B→Fe dative σ bonding interaction. This finding of the new quadruple bonding indicates that there might exist a wide range of boron-metal complexes that contain such high multiplicity of chemical bonds.

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COTTON, F. A., and R. POLI. "ChemInform Abstract: Thermal Reaction of Mo2I4(CO)8 with PMe2Ph, PEt2Ph, and Pyridine. Formation of Metal-Metal Quadruple Bonds vs. Disproportionation. X-Ray Crystal Structures of MoI3(PMe2Ph)2(POMe2Ph) and (PHEt2Ph)(MoI4(PEt2Ph)2)." ChemInform 18, no. 6 (February 10, 1987). http://dx.doi.org/10.1002/chin.198706230.

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46

COLE, N. F., D. R. DERRINGER, E. A. FIORE, D. J. KNOECHEL, R. K. SCHMITT, and T. J. SMITH. "ChemInform Abstract: REACTIONS OF CHLORO COMPLEXES OF DIMOLYBDENUM(II) CONTAINING QUADRUPLE METAL-METAL BONDS WITH BIDENTATE TERTIARY PHOSPHINES (C6H5)2P(CH2)NP(C6H5)2 (N = 1-3) AND (C6H5)2P(CH2)2AS(C6H5)2 IN ALCOHOL MEDIA. EFFECT OF LIGAND HYDROCARBON CH." Chemischer Informationsdienst 16, no. 42 (October 22, 1985). http://dx.doi.org/10.1002/chin.198542293.

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47

Heifets, E., and E. A. Kotomin. "The Adhesion Nature of Ag/MgO Interface: Hartree-Fock Study." MRS Proceedings 458 (1996). http://dx.doi.org/10.1557/proc-458-15.

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AbstractThe atomic and electronic structure of the Ag/MgO interface are calculated using the ab initio Hartree-Fock approach and a supercell model. The electronic density distribution is analyzed in detail for isolated and interacting slabs of a metal and MgO. The energetically most favorable adsorption position for Ag atoms is found to be above the O atoms. The binding energy is 0.20 eV (0.41 eV) for one and three Ag layers atop MgO substrate, respectively. The relevant equilibrium Ag-O distance is 2.64 Å(2.41 Å). Neither appreciable charge transfer in the interfacial region, nor considerable population of bonds between the silver layer and the insulating substrate take place. The adhesion energy arises mainly due to the electrostatic interaction of substrate atoms with a complicated charge redistribution in the metal monolayer, characterized by large quadrupole moments and electron density redistribution towards gap position in the middle of nearest Ag atoms.

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