Direct insertion of oxygen atoms into the backbonds of subsurface Si atoms using translational energies of oxygen atom beams

2007 ◽  
Vol 91 (3) ◽  
pp. 033504 ◽  
Author(s):  
Masahito Tagawa ◽  
Kumiko Yokota ◽  
Shinnosuke Tsumamoto ◽  
Chie Sogo ◽  
Akitaka Yoshigoe ◽  
...  
Keyword(s):  
Oxygen Atom ◽  
Oxygen Atoms

Nonclassical oxygen atom transfer reactions of an eight-coordinate dioxomolybdenum(vi) complex

2021 ◽  
Author(s):  
Leila G. Ranis ◽  
Jacqueline Gianino ◽  
Justin M. Hoffman ◽  
Seth N. Brown
Keyword(s):  
Oxygen Atom ◽  
Transfer Reaction ◽  
Transfer Reactions ◽  
Atom Transfer ◽  
Oxygen Atom Transfer ◽  
Oxygen Atom Transfer Reactions ◽  
Atom Transfer Reactions ◽  
Oxygen Atoms

Eight-coordinate MoO2(DOPOQ)2 can donate two oxygen atoms to substrates such as phosphines in a four-electron nonclassical oxygen atom transfer reaction.

AIM study on the transferability of the oxygen atom in linear ethers

2000 ◽  
Vol 78 (12) ◽  
pp. 1535-1543 ◽  
Author(s):  
Antonio Vila ◽  
Enrique Carballo ◽  
Ricardo A Mosquera
Keyword(s):  
Dipole Moment ◽  
Oxygen Atom ◽  
Potential Energy ◽  
Critical Points ◽  
Wave Functions ◽  
Electron Population ◽  
Alkyl Radicals ◽  
Energy Interaction ◽  
Interaction Dipole Moment ◽  
Oxygen Atoms

The integrated values of the electron population, electron energy, nucleus–electron potential energy interaction, dipole moment and volume of the oxygen atoms, and the main properties of the O—C bond critical points, were determined by employing the theory of atoms in molecules and 6-31++G**//6-31G* wave functions for a series of 25 unbranched alkyl monoethers. These results were used to assess the degree of approximate transferability of the oxygen atom along this series in terms of the particular alkyl radicals bonded to it. It has been found that a set of six different oxygen atoms is necessary to classify all the computed values. It can be established that the oxygen atoms bonded to propyl and larger radicals can be treated, in practice, as a transferable fragment, while those bonded to at least one smaller radical are specific. Though the total HF energy and the available experimental heats of formation are well fitted by a traditional additivity scheme that distinguishes only among O, CH2, and CH3 units, it has been found that the energy properties are influenced by the size of the molecule.Key words: transferability, AIM theory, ethers.

scholarly journals Crystal structure of β-Zn3(PO4)2

1967 ◽  
Vol 45 (20) ◽  
pp. 2303-2316 ◽  
Author(s):  
J. S. Stephens ◽  
C. Calvo
Keyword(s):  
Crystal Structure ◽  
Oxygen Atom ◽  
Lattice Parameters ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Basic Cation ◽  
Cation Coordination ◽  
Oxygen Atoms

β-Zn3(PO4)2 crystallizes in the monoclinic space group P 21/c with lattice parameters, a = 9.393(3) Å, b = 9.170(6) Å, c = 8.686(3) Å, β = 125.73(10)°, and Z = 4. The three independent cations are strongly ligated to 4, 5, and 5 oxygen atoms, with average Zn—O bond distances of 1.98 ± 0.09 Å, 2.10 ± 0.10 Å, and 2.08 ± 0.13 Å respectively. In addition there are two longer Zn—O distances of 2.51 Å and 2.55 Å in this structure. The PO4 groups exist as independent, nearly regular tetrahedra, with each oxygen atom ligated to two cations. Unlike the structures found for the α and γ phases of Zn3(PO4)2, which contain ribbons and sheets respectively as the basic cation coordination motif, the structure of β-Zn3(PO4)2 contains interconnected sheets.

Crystal Structure of α-Zn2V2O7

1973 ◽  
Vol 51 (7) ◽  
pp. 1004-1009 ◽  
Author(s):  
Ramanathan Gopal ◽  
Crispin Calvo
Keyword(s):  
Crystal Structure ◽  
Oxygen Atom ◽  
Bond Length ◽  
Fold Axis ◽  
Full Matrix ◽  
X Ray ◽  
R Value ◽  
The Individual ◽  
Zn Ions ◽  
Oxygen Atoms

α-Zn2V2O7 is monoclinic with lattice parameters a = 7.429(5), b = 8.340(3), c = 10.098(3) Å, β = 111.37(5)°, Z = 4 and space group C2/c. The structure was refined using a full matrix least-squares with 1034 reflections measured with a quarter-circle General Electric automatic X-ray diffractometer to a final R value of 0.066. The anion consists of a pair of VO4 tetrahedra sharing an oxygen atom which lies on a two-fold axis. The bridging V—O bond length is 1.775(4) Å while the three independent terminal ones are 1.728(4), 1.704(7), and 1.658(8) Å long. These bond lengths are consistent with the charge character around the individual oxygen atoms. The Zn ions are coordinated to five oxygen atoms with Zn—O bonds ranging from 1.973 to 2.088°Å. The structure is similar to that of α-CU2P2O7 and transforms to the thortvietite structure at about 615 °C.

Synthesis, IR and X-Ray Studies of Tetra(N,N′-tetraethyl-N″-benzoyl- phosphorictriamide)-tetra(μ-3-methoxo)-tetra(methanol)tetra-NickeI(II)

1998 ◽  
Vol 53 (8) ◽  
pp. 836-840 ◽  
Author(s):  
Vladimir A. Ovchynnikov ◽  
Vladimir M. Amirkhanov ◽  
Anatoliy A. Kapshuk ◽  
Tatyana Yu. Sliva ◽  
Tadeusz Glowiak ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Oxygen Atom ◽  
Metal Ion ◽  
Crystal And Molecular Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Octahedral Environment ◽  
Distorted Octahedral ◽  
Methoxy Groups ◽  
Oxygen Atoms

Abstract A new nickel(II) complex with N,N′-tetraethyl-N″-benzoylphosphortriamide (HL = C6H5C(O)N(H)P(O)(NEt2)2) of composition Ni4L4(OCH3)4·(HOCH3)4 (1) has been synthe­ sized. The crystal and molecular structure of 1 has been determined from the X-Ray diffraction data (tetragonal, space group P4̄21c with a = 17.000(2) Å, c = 15.338(3) Å, Z = 2; R = 0.0399 for 1412 unique reflections). The structure is made up of cubane-like tetramers. In the corners of a cube there are 4 atoms of nickel and 4 atoms of oxygen of methoxy groups. The nickel atoms are characterized by a slightly distorted octahedral environment, which consists of three oxygen atoms of methoxy groups, carbonylic and phosphorylic oxygen atoms of the ligand L-, and an oxygen atom of a methanol molecule. The ligands L- coordinate to the metal ion forming a chelate via the oxygen atoms of carbonylic and phosphorylic groups.

Kristallstrukturen der Komplexe Von Quecksilber(Ii)Iodid und -Thiocyanat mit L,13-Bis(8-Chinolyl)-L,4,7,10,13-Pentaoxatridecan („Kryptand 5“)

2000 ◽  
Vol 55 (10) ◽  
pp. 971-974 ◽  
Author(s):  
Joachim Pickardt ◽  
Sven Wiese
Keyword(s):  
Oxygen Atom ◽  
Chain Structure ◽  
Unit Cell ◽  
The Other ◽  
Ligand Molecule ◽  
Asymmetric Unit ◽  
Twofold Axis ◽  
A Chain ◽  
L 13 ◽  
Oxygen Atoms

AbstractReactions of 1,13-bis(8-chinolyl)-1,4,7,10,13-pentaoxatridecane (“Cryptand 5”) with HgX2 (X = I, SCN) yield crystals of [(cryptand 5)(HgI2)2] (1) and [(cryptand 5 )2{Hg(SCN)2}4] (2), resp. In both complexes two molecules of HgX2 are bound to one ligand molecule. 1 has symmetry Ci with the oxygen atom O(3 ) of the ether chain on a center of symmetry of the unit cell, each Hg atom is bound to the two I atoms, the N atom of the chinolyl residue, and one oxygen atom, O(1) and O(l)i, resp. of the ligand; neighbouring complex units are connected via iodine bridges thus forming chains. In 2 also two formula units of HgX2 are bound to one ligand molecule, but contrary to 1 the complex is not centrosymmetric. The Hg atoms of the two Hg(SCN)2 groups are co-ordinated differently: both are bound via sulphur atoms to two SCN-groups, one being a terminal SCN group, the other acting as a bridge to the Hg atom of a neighbouring complex unit. The first Hg atom is connected to a chinolyl N atom and too oxygen atoms, the second to a chinolyl N atom and three oxygen atoms. There are two independent complex units per asymmetric unit which are related by a non-crystallographic twofold axis, and which are connected via two SCN bridges. These “double molecules” are also interconnected by thiocyanate bridges, thus forming a chain structure

Crystal structure of Cd2V2O7

1967 ◽  
Vol 45 (20) ◽  
pp. 2297-2302 ◽  
Author(s):  
P. K. L. Au ◽  
C. Calvo
Keyword(s):  
Crystal Structure ◽  
Oxygen Atom ◽  
Lattice Parameters ◽  
The Other ◽  
Distorted Octahedron ◽  
Thermal Activity ◽  
Space Group ◽  
Bond Angles ◽  
Central Oxygen ◽  
Oxygen Atoms

Cadmium pyrovanadate crystallizes in the C2/m space group with lattice parameters a = 7.088(5) Å, b = 9.091(5) Å, c = 4.963(5) Å, β = 103°21(5)′, and z = 2. This crystal is an isostructure of the mineral thortveitite and thus the anion consists of a pair of centrosymmetrically related corner-sharing VO4 tetrahedra while the cation resides within a distorted octahedron of oxygen atoms. The anion has a linear V—O—V group, but, as with the isostructural pyrophosphates, the central oxygen atom shows an anomalously high thermal activity. The V—O bond distances are 1.76 Å for the inner bond and 1.70 Å for the terminal bond. The bond angles about the anion and cation are similar to those found for the other analogues of thortveitite.

Charge distributions and chemical effects. XXVI. Relationships between nuclear magnetic resonance shifts and atomic charges for 17O nuclei in ethers and carbonyl compounds

1982 ◽  
Vol 60 (2) ◽  
pp. 106-110 ◽  
Author(s):  
Marie-Thérèse Béraldin ◽  
Edouard Vauthier ◽  
Sándor Fliszár
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Oxygen Atom ◽  
Carbonyl Compounds ◽  
Electronic Charge ◽  
Atomic Charges ◽  
Chemical Effects ◽  
Opposite Trend ◽  
Nuclear Magnetic ◽  
Oxygen Atoms

The 17O nuclear magnetic resonance shifts of dialkylethers are linearly related to the electron populations on the oxygen atoms, in a range covering L ~ 130 ppm, showing that any increase of electronic charge at the oxygen atom is accompanied by a downfield nmr shift. The opposite trend is observed for the oxygen atoms of ketones and aldehydes.

scholarly journals Laboratory Simulation of Low Earth Orbit (LEO) Atomic Oxygen Effects

1996 ◽  
Vol 39 (2) ◽  
pp. 23-28
Author(s):  
George Caledonia ◽  
Robert Krech ◽  
David Oakes
Keyword(s):  
Oxygen Atom ◽  
Low Earth Orbit ◽  
Laboratory Simulation ◽  
Test Duration ◽  
Erosion Rates ◽  
Oxygen Effects ◽  
Ambient Oxygen ◽  
Atom Source ◽  
Oxidative Effects ◽  
Oxygen Atoms

Our pulsed fast oxygen atom source has been used extensively over the last 9 yr to investigate the effects of ambient oxygen atoms that impact materials placed in LEO. During this period, we have irradiated over 2000 material samples with 8 km/s oxygen atoms generated in our source. Typical irradiance level is 3 × 1020 O atoms/cm2 although some materials have been irradiated to fluence levels as high as 6 × 1021 O atoms/cm2. In this paper, we review the operating principles and characteristics of our source along with the diagnostic and handling procedures appropriate to material testing. We then present representative data on the velocity dependence of oxygen atom erosion rates (the PSI source provides oxygen atoms tunable over the velocity range of 5 to 12 km/s) as well as the dependence on material temperature. Specific examples of nonlinear oxidative effects related to surface contamination and test duration will also be provided.

Synthesis and Structure of (17-Hydroxy-4,4,9,9,11- pentamethyl-5,8,12,13,15-pentaazaheptadec- 11-en-2-one hydrazone)nickel(II) Perchlorate; a Compound with a Hexadentate gem-Diamine Ligand

1997 ◽  
Vol 50 (1) ◽  
pp. 69 ◽  
Author(s):  
Neil F. Curtis ◽  
Olga P. Gladkikh
Keyword(s):  
Oxygen Atom ◽  
Secondary Amine ◽  
Ground State ◽  
Starting Material ◽  
Octahedral Coordination ◽  
Triplet Ground State ◽  
Triclinic Space Group ◽  
Space Group ◽  
Oxygen Atoms

(4,4,9,9-Tetramethyl-5,8-diazadodecane-2,11-dione dihydrazone)nickel(II) perchlorate reacts with 2- aminoethanol and methanal to form blue-violet (17-hydroxy-4,4,9,9,11-pentamethyl-5,8,12,13,15- pentaazaheptadec-11-en-2-one hydrazone)nickel(II) perchlorate. The structure of a methanol solvate was determined [C18H43Cl2N7NiO10, Mr 647·2, triclinic, space group P -1, a 8·992(7), b 10·86(2), c 15·02(1) Å, α 79·95(2), β 76·85(5), γ 78·83(2)°, Z 2, R 0·0637 for 2992 reflections]. The ligand has one terminal hydrazone function of the starting material linked to the 2-aminoethanol residue by a gem-diamine function derived from methanal. The ligand is hexadentate, with the triplet ground state nickel(II) ion in octahedral coordination by three secondary amine and two hydrazone nitrogen atoms and a hydroxy oxygen atom, with the terminal hydrazone nitrogen and the hydroxy oxygen atoms coordinated trans.

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