Manganese binary compounds

Manganese combines with several metals at elevated temperatures forming binary compounds in varying compositions. Such metals include Al, Zn, Ni, Sn, As, Sb, Be, Pd, and Au. 

Structural data are available (Table 30) for a range of binary, ternary and quaternary sulfides of manganese, almost invariably Mn", and these set the scene for the structures to be expected in the compounds with the more discrete polyhedra.319 Indeed, the structural pattern is established in the simple binary compound MnS. Whereas, the stable modification of this (a-MnS) is green and has the cubic rock salt structure with [MnS6] octahedra, the well-known flesh-coloured precipitates of the qualitative analysis system are metastable / - and y-modifications, which have [MnS4] tetrahedra with respectively the zinc blende or diamond (cubic) and wurtzite (hexagonal) structures. And so, in the rest of the known solids, there are almost equal numbers of four-coordinate tetrahedra and six-coordinate octahedra with no other polyhedra having been detected. 

Group 7 (Mn, Tc, Re). No binary compounds are formed with manganese, and no homogeneous product could be prepared. Technetium reacts with W, forming a solid solution and a a-phase (WTcs). Timgsten-technetium alloys are of practical interest as superconductors. 

The only binary compound of manganese (III) with the halides stable at room temperature is Mnp3. Hydrated salts of the anions MnF4 , MnFs, and MnFg... 

During Werner s time compositional nomenclature for binary compounds had already been agreed upon in much the same way as today, and names such as manganese dichloride and manganese monooxide were in common use to express information about stoichiometric compositions only. For complex compounds, this type of nomenclature had simply b n extended as in the notational example 3 KCN,Fe(CN)3. Werner realized that diis notation could be modified to became a nomenclature including structural information, when this was available, and potassium hexacyanoferriate is his ingenious proposal (2). This is an example of what is today referred to as additive nomenclature or coordination nomenclature, as opposed to the substitutional nomenclature of organic chemistry. 

The fuels are finely powdered metals (2.0-10.0 g) among which titanium, zirconium, manganese, tungsten, molybdenum and antimony are very common. Sometimes, non-metal powders such as boron and silicon (for fast burning delays), binary alloy powders such as ferrosilicon, zirconium-nickel, aluminum-palladium and metal compounds such as antimony sulfide, calcium silicide etc. are also used. 

In a brief survey of other simple binary carbonyls we find that the compounds M(CO)6(M = Cr, Mo, W) and Ru3(CO)12 have only minimal catalytic activity for autooxidizing alcohols or ketones. The compounds Fe(CO)5 and Fe3(CO)12 are decomposed completely when we try to use them as catalysts. When the compound Mn2(CO)i0 is used, there is a considerable enhancement in acid formation. During this reaction there is extensive decomposition to manganese dioxide, and we believe that this compound is the one primarily involved in the catalytic oxidation. 

In addition to the estimated properties, we measured the thermochemistry of several important vapor species. These measurements were conducted in a Knudsen effusion cell using special line-of-sight vaporization under subambient pressures with flowing O2 and H2O vapor mixtures [4]. The gaseous species over silica [5], manganese oxide [6], lanthana, alumina, and palladium metal were detected and relative partial pressures measured as a function of temperature. These vapor pressure measurements were calibrated by using the known metal atom or binary metal oxide volatility as a calibration source. Oxide species concentrations were measured relative to that of a reference compound, e.g., metal atom. The identification of oxide and hydroxide compounds was facilitated by Ae technique of threshold electron ionization [7]. These data were then evaluated using estimated entropy functions and the third law temperatures. 

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