Showing papers on "Oxidation state published in 1977"
TL;DR: In this article, the binding energy of the Zn 2P/sub 3/2/ electron in sludge was found to be 3.5 +- 0.1 on the Pauling scale.
Abstract: Electron Spectroscopy for Chemical Analysis (ESCA) was used to provide information concerning the chemical bonding of zinc and copper present in the sludge obtained from the Dayton, Ohio sewage treatment plant. The binding energy of the Zn 2P/sub 3/2/ electron in sludge when placed under a vacuum of 10/sup -7/ Torr was 1023.8 +- 0.2 eV and the binding energy of the Cu 2p/sub 3/2/ electron in the sludge under similar conditions was 937.2 +- 0.3 eV. These energies are characteristic of both Zn and Cu being in the positive two oxidation state. The electronegativity of the ligand attached to either of these metals was found to be 3.5 +- 0.1 on the Pauling scale. This indicates that Zn and Cu exist in similar compounds, that the ligand binding site is oxygen, and that the possible compounds include carbonate, carboxylate, phosphate, nitrate, silicate, and/or oxide. ESCA, when used in conjunction with other methods, offers excellent potential for more specifically identifying the chemical form of metal in sludge or sludge mixtures.
438 citations
TL;DR: In this paper, the surface oxides produced from potentiostatic and galvanostatic oxidation of Pt electrodes in HClO4 and H2SO4 were examined using X-ray photoelectron spectroscopy.
168 citations
TL;DR: The effect of substituents on pi radical reactions of para-substituted tetraphenylporphyrins was investigated by cyclic voltammetry in methylene chloride and the value of p appears not to be directly affected by the central metal oxidation state or the overall charge on the complex.
58 citations
TL;DR: In this paper, the oxidation state of the central atom M in intercalation compounds of the form C n MF x can be determined by examination of the chemical shift of the fluorine magnetic resonance.
48 citations
TL;DR: In this paper, the X-ray photoelectron spectra (metal and halogen energy levels) have been recorded for binary halides of indium in the +I, +II, and +III states.
Abstract: The X-ray photoelectron spectra (metal and halogen energy levels) have been recorded for binary halides of indium in the +I, +II, and +III states, and for anionic halide complexes of indium(I) and (III). The results are internally consistent in terms of the relation between metal and ligand levels, but lattice effects prevent any detailed interpretation of indium levels in terms of oxidation state, ligand electronegativity, and/or coordination number.
34 citations
Book•
01 Jan 1977TL;DR: Sulfur-containing polymers vary from highly reactive to chemically inert substances; they can have high softening points or be viscous oils, be thermally stable or not.
Abstract: Owing to the fact that sulfur can exist in different oxidation states and that in each oxidation state it can form different functions, there exist many different sulfur-containing chemical functions with a widespread array of chemical and physical properties. Consequently, sulfur-containing polymers vary from highly reactive to chemically inert substances; they can have high softening points or be viscous oils, be thermally stable or not. Some of these polymers have found commercial applications, others are of academic interest.
29 citations
TL;DR: In this article, it was shown that the 1-oxidation state of the alkali metals exists under a variety of conditions, and it can no longer be any doubt that it exists.
Abstract: There can no longer be any doubt that the 1- oxidation state of the alkali metals exists under a variety of conditions.
29 citations
TL;DR: In this paper, a brief review of the X-ray photoelectron spectra (XPS) of a variety of molybdenum oxides and their complexes in which the central metal atom possesses a formal oxidation state anywhere between (V) and (II).
Abstract: A brief review is presented of the X-ray photoelectron spectra (XPS) of a variety of molybdenum oxides and molybdenum-containing heterogeneous catalysts which have been reported during the last five years (1971–1976). A more detailed account is given of Mo(3d) and Cl(2p) binding energies of molybdenum halides and their complexes in which the central metal atom possesses a formal oxidation state anywhere between (V) and (II). A correlation exists between the Mo(3d) and Re(4f) binding energies of molybdenum and rhenium chloride complexes which possess very similar molecular structures (e.g. MoCl4(PPh3)2 and ReCl4(PPh3)2) or in which the metal ions are formally isoelectronic (e.g. Mo2Cl4(PEt3)4 and Re2Cl6(PEt3)2). As a result of differences between the Cl(2p) binding energy spectra of α- and β-MoCl2, a detailed study has been made of the chemical reactivity of these two halides. Unlike α-MoCl2, which contains a hexanuclear cluster of molybdenum atoms (Mo6Cl12), β-MoCl2 is formulated as having a polymeric structure (Mo2Cl4)n in which metal-metal bonded Mo2 units are present.
20 citations
18 citations
13 citations
TL;DR: In this article, a platinum/platinum-rhodium (20%) bimetallic electrode with a small constant applied current was used for end-point detection, and the average standard deviation was 0.35% for iron(II) and 0.22% for total iron.
TL;DR: In this article, the rate constants for quenching of chlorophyll-a singlets and triplets by a series of manganese complexes have been measured in fluid solution.
Abstract: The rate constants for quenching of chlorophyll-a singlets and triplets by a series of manganese complexes have been measured in fluid solution. Quenching efficiency correlates with the oxidation state of the central manganese atom : 4 > 3 > 2, and, for manganese (II) complexes, the degree of conjugation of the complexing ligand makes an important contribution towards the magnitude of the quenching rate constants. Ion-pair formation occurs with the higher oxidation state quenchers but not with manganese (II). Here, charge transfer interactions are implicated in the quenching reaction and the collision complex provides a means of non-radiative decay.
Patent•
08 Nov 1977
TL;DR: Clean etchings at high rates are obtained using a solution containing sulfuric acid, hydrogen peroxide, a catalytic amount of a selenium compound of a +4 oxidation state and a secondary or tertiary alcohol.
Abstract: Clean etchings at high rates are obtained using a solution containing sulfuric acid, hydrogen peroxide, a catalytic amount of a selenium compound of a +4 oxidation state and a secondary or tertiary alcohol.
Patent•
08 Dec 1977TL;DR: In this article, a process for the oxidation of hydrogen to water in the presence of elemental nitrogen with minimal oxidation thereof is described, which comprises combining the hydrogen with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the synthesis of hydrogen.
Abstract: A process for the oxidation of hydrogen to water in the presence of elemental nitrogen with minimal oxidation thereof which comprises combining the hydrogen with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidation of hydrogen to water and passing the resulting mixture over a ceramic catalyst of the following empirical formula at a temperature between about 100° C and about 1,000° C; w.sub.k X.sub.n J(1-k-n).sup.ZO (3±m) Wherein W is Zirconium, Tin or Thorium or mixtures thereof; X is an alkaline earth metal or mixture thereof; J is scandium, yttrium, a rare-earth element or mixture thereof; Z is a metal of the first transition series of a mixture thereof, at least 0.01% of said metal having an oxidation state other then +3; k is a number having a value between 0 and about 0.1; m is a number having a value of from 0 to about 0.26; and n is a number having a value from 0 to about 0.51, provided when n has a value of 0, k has a value between 0 and about 0.05.
Patent•
08 Nov 1977
TL;DR: Clean etchings at high rates were obtained using a solution containing sulfuric acid, hydrogen peroxide, a catalytic amount of a selenium compound of a +4 oxidation state and t-butyl hydroperoxide as mentioned in this paper.
Abstract: Clean etchings at high rates are obtained using a solution containing sulfuric acid, hydrogen peroxide, a catalytic amount of a selenium compound of a +4 oxidation state and t-butyl hydroperoxide.
TL;DR: In this paper, a linear correlation was obtained between formal S oxidation state and S 2p ionization potential for both the experimental and theoretical results, leading to an assignment of an S oxidation states of 4 in bis-(2-carboxyphenyl) sulphur dihydroxide dilactone.
Abstract: Inner shell ionization potentials have been evaluated for some diphenyl substituted (“model” unsubstituted) sulphides, sulphoxides, sulphones and sulphuranes by means of X-ray photoelectron spectroscopy (non-empirical mo calculation)A good linear correlation is obtained between formal S oxidation state and S 2p ionization potentials for both the experimental and theoretical results, leading to an assignment of an S oxidation state of 4 in bis-(2-carboxyphenyl) sulphur dihydroxide dilactone
TL;DR: In this article, it was shown that reactions with π-acids and some π complexes such as CpTiX3, CP2MCl2 (M Ti, Zr, Hf, V) take place with oxidation of the manganese atom electron transfer to the acceptor molecule and the formation of the cation-radical of the donor molecule.
Patent•
01 Apr 1977Abstract: Ionic conductivity in ternary chalcogenides of the form ABx Cy, where A is a metallic atom with atomic number no greater than 55 which has a +1 oxidation state, B is a group III A metallic atom and C is a group VI A atom, has been observed. This ionic conductivity makes the compounds useful as components in electrochemical cells, e.g., electrolytes and electrodes.
TL;DR: In this paper, a thin layer hydrated molybdenum oxide (oxidation state IV or V) has been deposited electrochemically on a variety of substrates, e.g., polycrystalline tin oxide coated glass.
Abstract: Thin layer hydrated molybdenum oxide (oxidation state IV or V) has been deposited electrochemically on a variety of substrates, e.g., polycrystalline tin oxide coated glass. It is capable of existing in an oxidized or reduced form and its equilibrium properties are described by a Nernst-like relationship. Experimentally the activities of the two forms are found to depend on a power function of their concentrations. The equilibrium position is also a function of pH. The rate of oxidation is described by a kinetic rate law of at least second order. Slow self-oxidation also occurs over a period of hours possibly due to the reduction of H+.
Patent•
08 Dec 1977TL;DR: In this paper, a process for the oxidation of ammonia to nitrous oxide in the presence of elemental nitrogen with minimal oxidation thereof is described, which comprises combining the ammonia with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidization of ammonium to Nitrous oxide and passing the resulting mixture over a ceramic catalyst.
Abstract: A process for the oxidation of ammonia to nitrous oxide in the presence of elemental nitrogen with minimal oxidation thereof which comprises combining the ammonia with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidation of ammonia to nitrous oxide and passing the resulting mixture over a ceramic catalyst of the following empirical formula at a temperature between about 100° C and about 400° C.; w.sub.k X.sub.n J(1-K-n).sup.ZO (3±m) Wherein W is Zirconium, Tin or Thorium or mixtures thereof; X is an alkaline earth metal or mixture thereof; J is scandium, yttrium, a rare-earth element or mixture thereof; Z is a metal of the first transition series or a mixture thereof, at least 0.01% of said metal having an oxidation state other than +3; k is a number having a value between 0 and about 0.1; m is a number having a value of from 0 to about 0.26; and n is a number having a value from 0 to about 0.51, provided when n has a value of 0, k has a value between 0 and about 0.05.
TL;DR: In this article, it was shown that the reactive loci of sulfonyl chlorides reside at sulfur and since the formal oxidation state of the sulfur atom is +6, most of their reactions are characterized by hard-hard interactions (charge-controlled), as exemplified by the sulfonylation of alcohols and amines.
TL;DR: In this paper, the authors dealt with the chemical behavior of the fluoro-complexes of Ti 4+ and Nb 5+ under high temperature and pressure and focused on the concentration effect of HF on the crystalline forms of hydrolysis products.
TL;DR: X-ray photoelectron spectrometry was applied to evaluate the correct oxidation number of copper in complexes with 2-thiouracil, 6-amino-2-thaviouracil and 6-methyl-2 -thiourACil, in which Cu had the formal oxidation state +I.
Abstract: X-ray photoelectron spectrometry was applied to evaluate the correct oxidation number of copper in complexes with 2-thiouracil, 6-amino-2-thiouracil and 6-methyl-2-thiouracil. Regardless of the mode of preparation exclusively Cu(I) was bound to the different thiouracil compounds, producing one homogeneous signal of the Cu2p3/2 electrons at 932.5 eV. Upon oxidation with H2O2, a typical Cu(II) satellite appeared in the main signal of the Cu2p3/2 level was shifted to higher binding energy values. The reaction of Cu(II) with thioracil yielded identical complexes as above, in which Cu had the formal oxidation state +I. During this reaction portions of the thiouracil were oxidized to 2,2'-dithiobis(4-pyrimidinol) [bis(4-hydroxy-2-pyrimidinyl)disulphide], as seen by the shifted sulphur 2p signals to 163.5 eV. After treating the Cu-thiouracil complexes with H2O2, the simultaneous presence of sulphur species having the oxidation states RStheta (161 eV), RSSR (163.5 eV) and RSOtheta3 (168.5 eV) is indicated by the ESCA signals monitored.
Patent•
08 Dec 1977TL;DR: In this article, a process for the oxidation of sulphur dioxide to sulfur trioxide in the presence of elemental nitrogen with minimal oxidation thereof is described, which comprises combining the sulfur dioxide with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidization of sulfur dioxide to sulphur trioxide and passing the resulting mixture over a ceramic catalyst of the following empirical formula at a temperature between about 120° C and about 800°.
Abstract: A process for the oxidation of sulphur dioxide to sulfur trioxide in the presence of elemental nitrogen with minimal oxidation thereof which comprises combining the sulfur dioxide with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidation of sulfur dioxide to sulfur trioxide and passing the resulting mixture over a ceramic catalyst of the following empirical formula at a temperature between about 120° C and about 800°; W.sub.k X.sub.n J(1-k-n).sup.ZO (3±m) wherein W is Zirconium, Tin or Thorium or mixtures thereof; X is an alkaline earth metal or mixture thereof; J is scandium, ytrrium, a rare-earth element or mixture thereof; Z is a metal of the first transition series or a mixture thereof, at least 0.01% of said metal having an oxidation state other than +3; k is a number having a value between 0 and about 0.1; m is a number having a value of from 0 to about 0.26; and n is a number having a value from 0 to about 0.51, provided when n has a value of 0, k has a value between 0 and about 0.05.
Patent•
08 Dec 1977TL;DR: A process for the oxidation of hydrogen sulfide to sulfur trioxide in the presence of elemental nitrogen with minimal oxidation thereof is described in this article, which comprises combining the hydrogen sulphide with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidization of the resulting mixture over a ceramic catalyst.
Abstract: A process for the oxidation of hydrogen sulfide to sulfur trioxide in the presence of elemental nitrogen with minimal oxidation thereof which comprises combining the hydrogen sulfide with a predetermined amount of oxygen containing gas to give at least 1% stoichiometric excess of oxygen for the oxidation of hydrogen sulfide to sulfur trioxide and passing the resulting mixture over a ceramic catalyst of the following empirical formula at a temperature between about 100° C and about 700° C.; w.sub.k X.sub.n J(1-k-n).sup.ZO (3±m) wherein W is Zirconium, Tin or Thorium or mixtures thereof; X is an alkaline earth metal or mixture thereof; J is scandium, yttrium, a rare-earth element or mixture thereof; Z is a metal of the first transition series or A mixture thereof, at least 0.01% of said metal Having an oxidation state other than +3; k is a number having a value between 0 and about 0.1; m is a number having a value of from 0 to 0.26; and n is a number having a value from 0 to about 0.51, Provided when n has a value of 0, k has a value between 0 and about 0.05.
TL;DR: In this article, the X-ray photoelectron spectra of α-Sb2O4 and BaBiO3 were analyzed and the mixed-valency character of these oxides was found only after careful pretreatment of the samples in situ.
Abstract: X-Ray photoelectron spectra of the metal(III)–metal(V) oxides α-Sb2O4 and BaBiO3 are reported. Indications of ‘mixed-valency’ character in the metal core-electron spectra could be found only after careful pretreatment of the samples in situ. Under normal conditions both compounds appear to have surface phases containing just the lower oxidation state.
TL;DR: In this article, a thin layer hydrated molybdenum oxide (oxidation state IV or V) has been deposited electrochemically on a variety of substrates, e.g., polycrystalline tin oxide coated glass.
Abstract: Thin layer hydrated molybdenum oxide (oxidation state IV or V) has been deposited electrochemically on a variety of substrates, e.g., polycrystalline tin oxide coated glass. It is capable of existing in an oxidized or reduced form and its equilibrium properties are described by a Nernst-like relationship. Experimentally the activities of the two forms are found to depend on a power function of their concentrations. The equilibrium position is also a function of pH. The rate of oxidation is described by a kinetic rate law of at least second order. Slow self-oxidation also occurs over a period of hours possibly due to the reduction of H+.