Hexacarbonyls spectrum

Reaction of PCTFE with a stoichiometric amount of chromium hexacarbonyl in DMF at 95°C for 5 days under a nitrogen atmosphere, followed by hydrolysis results in the formation of a brown-black polymer. Analysis of the infrared data indicates that carbonylation does indeed occur (Equation 11). The infrared absorption spectrum shows a large decrease in the C-Cl stretch at 970 cm-1 with a concomitant appearance of a very strong band in the carbonyl stretching region centered at 1680 cm1. There is also a broad band centered at 3490 cm-1 in the hydroxyl stretching region and two bands of moderate intensity... 

Electronic Spectra of d6 Metal Hexacarbonyls and Hexacyanides. A. Metal Hexacarbonyls-—The electronic spectrum of Cr(CO)6 in the vapor phase shows two intense absorption bands at 35,780 and 44,480... 

Reactions of Fes(CO)i2 with alkyl isocyanates or alkyl azides give the N,N dialkylureylene-diiron hexacarbonyls (RN)2COFe2(CO)6 (33) mass spectroscopy was used for the initial identification of these compounds 66>. The mass spectrum of the diphenyl derivative... 

In the course of preparing [Cl0II8Mn(CO)3]2 Bird and Churchill (22) isolated azulenedimanganese hexacarbonyl C10H8Mn2(CO)6. Its mass spectrum shows the molecular ion and fragments corresponding to stepwise loss of the six carbonyl groups. 

The charge on a carbonyl complex is also reflected in its infrared spectrum. Five isoelectronic hexacarbonyls have the following C—O stretching bands (compare with v(CO) = 2143 cm i for free CO) ... 

Tungsten hexacarbonyl (2.8) contains six equivalent CO ligands. With reference to Table 2.3, suggest what you would expect to observe in the NMR spectrum of a C-enriched sample of W(CO)g. 

In the case of [Ni(CO)4], [Fe(CO)s], and [M(CO)J where M = Cr,Mo,W, spectra of negative ions were also investigated. For M(CO) -type carbonyls, the following ions were observed M(CO) i, M(CO) 2 M(CO) , M. The parent ions are not stable, because the extra electron must occupy an antibonding molecular orbital. An exception is V(CO)6, a 17e complex, in which the electron occupies a nonbonding orbital. [V(CO)6]- is easily formed in solution it was also found in the mass spectrum of vanadium hexacarbonyl. 

Flash-photolysis studies of the hexacarbonyls Cr(CO)g, Mo(CO)g and W(CO)g are, like previous years, still abundant Nayak and Burkey have found that there are low quantum yields for Cr(CO)g substitution in fluorocarbon solvents - which provides yet more evidence that metal-fluorocarbon interactions are very weak There have been estimates made of solvent-metal bond strengths in (Solvent)M(CO)5 complexes (Solvent = Benzene [M = Mo, W] and Tetrachloromethane [M = Cr]) and the photolysis of W(CO)g in the presence of hex-l-ene has been reported Flash-photolysis studies of the photochemical reactions of silanes with Cr(CO)g have been published Using time-resolved infrared spectroscopy RIR), Turner and co-workers have captured the IR spectrum of the MLCT excited state of W(CO)5(4-cyanopyridine) which rapidly decays to W(CO)5. The excited state of W(CO)5(4-cyanopyridine) is relatively long lived, which makes the experiment possible. This reporter will be interested to see how this technique develops. 

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