IR stretching frequency

The IR stretching frequencies o(SN) and o(SF) occur at higher wave numbers and the S-N and S-F distances are significantly shorter in the octahedral cations [M(NSF)6] than those in the free ligand, indicating an increase in S-N and S-F bond strength upon coordination. 

TABLE 4. Selected IR stretching frequencies of sulfone and sulfoxide groups in thiirane and thiirene dioxides and oxides... 

TABLE 9. Influence of H-bonding on IR stretching frequencies of sulphoxides and sulphones... 

Table Stoichiometry and corresponding IR stretching frequencies of different metal carbonyls. Charges for monocarbonyls were estimated from the correlation between IR stretching frequency and charge of the metal center as inferred from theoretical calculations (for details see [15,17]) ...

Compound Bond Type O O Bond Length (A) 0-0 Bond Order IR Stretching Frequency (cm-1)... 

The 1,2-oxaborolide anion (Figure 1), an analog of furan, has been prepared by two different routes and sandwich complexes with ruthenium and manganese 136, 137 have been characterized.153 Comparison of IR stretching frequencies suggests that oxaborolide is a weaker electron donor and better electron acceptor than cyclopentadienyl. 

For rhodium complexes the IR stretch frequency of ram-RhClL2(CO) has been used [14],... 

Following the trend towards lower carbonyl IR stretch frequencies, branching alpha to the amide carbonyl (Table 5, entries 53, 54, 62, 63 and 65) affects the shifts for mutagens and hydroxamic esters similarly and causes a marked downfield shift of up to 6 ppm relative to the acetamide substrate (Table 5, entry 60). These effects, as well as the smaller than expected downfield shift with ferf-butyl and neopentyl side chains are, as with the Ai-chlorohydroxamic esters, due to the combined influence of a stabilizing alkyl inductive effect together with destabilizing desolvation of the polar form of the amide carbonyl ". 

The properties of these compounds have been discussed previously.2 The complexes are green oils or solids readily soluble in organic solvents. They are stable in air for short periods of time but are best stored under nitrogen at temperatures below 0°. The characteristic IR stretching frequencies for these compounds are listed below. 

The presence of two carbonyl conformers has also been observed (70MI5 84MI5) in the N-acyl derivatives of benzothiazolone 112 and benzooxa-zolone 113. In benzothiazolone derivatives 112, IR stretching frequencies... 

Selected Distances (A), Angles (Degrees), and IR Stretching Frequencies (v, cm 1) Calculated for the Different Steps of Reaction 1, at the B3LYP/... 

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