Carbon vibrational spectra

Korzeniewski C, Pons S, Schmidt PP, Severson MW. 1986. A theoretical analysis of the vibrational spectrum of carbon monoxide on platinum metal electrodes. J Chem Phys 85 4153-4160. 

Diamond is crystallized in cubic form (O ) with tetrahedral coordination of C-C bonds around each carbon atom. The mononuclear nature of the diamond crystal lattice combined with its high symmetry determines the simplicity of the vibrational spectrum. Diamond does not have IR active vibrations, while its Raman spectrum is characterized by one fundamental vibration at 1,332 cm . It was found that in kimberlite diamonds of gem quality this Raman band is very strong and narrow, hi defect varieties the spectral position does not change, but the band is slightly broader (Reshetnyak and Ezerskii 1990). 

Protonation of 21 yields H2Os,0C(CO)24 (5 7). The crystal structure of the dihydride has not been determined, but analysis of the vibrational spectrum of the cluster in the region associated with motion of the interstitial carbon atom has led to the conclusion that the symmetry of 21 is reduced on protonation, probably by protonation of the central Os6 octahedron (see Section VI,A) (57). Cluster 21 also reacts with iodine to yield sequentially [Osl0C(CO)24I]", 22, and Os.oCfCO), 23, the result of electrophilic attack by 1+ on the dianion [Eq. (16)] (55). 

In the next sections we discuss the available data on the electrochemical Stark effect on the vibrational spectrum of adsorbed carbon monoxide and adsorbed sulfate ions at platinum. 

The interfullerene covalent bond lengths are about 1.6 A, i.e. quite close to usual CT bond lengths. MAS spectra [63] also show evidence for carbon atoms with predominantly sp character at the bonding sites. Polymerization deforms the C(jo ions and elongates them along a. The appearance of new lines in the infrared vibrational spectrum during [39] the transformation from the fee phase to the polymer clearly demonstrates the lower symmetry of the C o ions in the polymer. 

During infrared-visible SFG studies of carbon monoxide on Pt(lll) in the 10 -700 Torr pressure range, dramatic changes in the vibrational spectrum of surface species were observed at high CO pressures. The vibrational signatures of the adsorbed species implicate the formation of carbonyl-platinum cluster analogs coadsorbed with an incommensurate CO overlayer. 

The vibrational spectrum of carbon monoxide on metal surfaces has been studied from both theoretical and experimental spectroscopic perspectives. Althou it is not necessary to review these results within the scope of tUs chapter, a summary of the most important aspects will serve as a guide for the application of the technique to colloidal metals. 

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