Stretching coordinates hydrogen bonds, bond vibrations

The presence of an OH group at the 2-position of the phenyl ring of the BA residue effects a bathochromic shift as shown in Table 1. This has been attributed to intramolecular hydrogen bond formation, with the benzenoid form (5) preferred over the quinoid one (6). In these compounds, the phenolic C—O stretching vibration occurs between 1288 and 1265 cm-1. Upon coordination to... 

In a separate study, Myneni et al. (1998) used IR data to examine the coordination of As(V) in Mg, Co, Na, and Fe arsenate salts. The authors determined that hydrogen bonding, which is substantial in these materials, had little effect on the position of bands corresponding to vibrations within the arsenate tetrahedron. However, the authors determined that the position of the peak assigned to the synunetric stretch of the As-OH bond increases... 

The CC and CO vibrations are also sensitive to the molecular environment by virtue of electrostatic and hydrogen bonding interactions. The frequencies of phenoxyl and tyrosyl radicals complexed by macrocyclic hgands and generated in wVo were measured by resonance Raman and FTIR techniques. Thus a selective enhancement of the vibrational CC and CO stretch modes of the phenoxyl chromophores in metal-coordinated radical... 

Hence, the double-proton transfer was assumed to proceed via a concerted mechanism, with the one-dimensional kinetic-energy matrix appropriate to one particle of twice the proton mass. A similar model is widely used to analyze the vibrations of cyclic hydrogen-bonded dimers (for example, see Ref. [59]). The O -O coordinate in this case symbolizes the intermolecular stretching of a doubly H-bonded system. The problem of the double-proton transfer for the benzoic acid dimer is thereby reduced to a problem conceptually similar to that for a single O -H -O entity except for the denoted light atom mass and consequences of the asymmetric 2D PES. 

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