Bridging intramolecular vibration

Schwarzer D, Kutne P, Schroder C, Troe J (2004) Intramolecular vibrational energy redistribution in bridged azulene-anthracene compounds ballistic energy transport through molecular chains. J Chem Phys 121 1754... 

Here Efn(0) refers to the /th excited state of a free molecule in the crystal a n + (aQ is the Bose operator of creation (annihilation) of an intramolecular vibrational excitation in the nth molecule M2(k) refers to the energy of an optical phonon with the wave vector k connected with proton oscillations in the O H O bridge (bk) is the Bose operator of phonon creation (annihilation) and is the coupling energy between the molecular excitation and phonons. 

Weakening of the intramolecular CO bond by potassium has been observed in vibrational spectra of CO on Ni [48], Ru [49], Rh [50], and Pt [51]. Figure 9.13 shows a series of electron energy loss spectroscopy (EELS) spectra of CO adsorbed on a Pt(lll) surface promoted with 9% potassium, as reported by Pirug and Bonzel [51]. In order to fully appreciate these results, we should know that CO on a dean Pt(lll) surface yields two CO adsorption states characterized by CO stretch frequendes of 2120 and 1875 cm-1, belonging to linear and bridge-bonded CO, respectively. 

Compounds with an intramolecular hydrogen bridge (IMHB), such as 2-(2-hydroxyaryl)-l,3,5-triazines, are used widely for the photostabilization of polymers. They absorb harmful UV radiation and transform it, via a very efficient ESIPT within the IMHB, into vibrational energy. 

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